Online advertising and Ad tech glossary

The Xandr Online Advertising and Ad Tech Glossary provides definitions of common and important terms relating to online advertising, ad tech, and ad trading. 



When a user signs up, makes a purchase, or performs some other desired action in response to an ad displayed on the Internet. Also called a conversion or action. See also CPA.

ad agency

A company that provides services such as planning, creating, buying, and tracking advertisements and ad campaigns on behalf of a client. Often, people confuse media agencies, which are allocators of marketers' spending across channels – with creative agencies, which are responsible for the creation of actual ads and campaign content.

ad call

When an open slot of ad space is available on the Internet, a user's browser sends requests to ad exchanges or ad servers to send an ad. This request is known as an ad call. Ad calls include information from browser cookies and ad tag information such as publisher ID, size, location, referring URL, and other specifications and data needed for the ad to serve. See also ad tag.

ad pod

An individual ad pod is a group of ads expected to play back-to-back in one commercial ad break. It is similar to how consumers experience commercial ad breaks in broadcast television. An ad pod can be of varying lengths and can be inserted at any point in a stream of content (pre, mid, or post).

AdChoices icon

"AdChoices" is part of the Digital Advertising Alliance (DAA) Self-Regulatory Program for Online Behavioral Advertising. The clickable icon associated with this program (technically named the "Advertising Option Icon") can be placed overtop of creatives to give consumers a better understanding of and greater control over ads that are customized based on their online behavior. See the icon and read more at the DAA's website.

ad exchange

An ad trafficking system through which advertisers, publishers, and networks meet and do business via a unified platform. An ad exchange allows advertisers and publishers to use the same technological platform, services, and methods, and "speak the same language" in order to exchange data, set prices, and ultimately serve an ad.

advertising Id

AdId is a unique, user-resettable ID for advertising, provided by Google Play services.

ad network

A company that serves as a broker between a group of publishers and a group of advertisers by aggregating inventory and audiences from numerous sources in a single buy. Ad networks traditionally aggregate unsold inventory from publishers in order to offer advertisers a consolidated and generally less expensive pool of impressions, but they can have a wide variety of business models and clients. In the context of ad trafficking and ad tech, the term "network" is generally taken to mean an ad network.

ad server

The computer or group of computers responsible for actually serving creatives to websites, or for making decisions about what ads will serve. An ad server may also track clicks on ads and other data. Major publishers, networks, and advertisers sometimes have one or more of their own ad servers. For example, Xandr offers several types of ad servers, each with different capabilities and features.

ad tag

A piece of HTML on a webpage that will contact an ad server and ask for an ad. The tag informs the browser to open a small window (say, 468×60 pixels), and place whatever content is returned from some location (like×60&s) in that window. Note that ad tags are related, but not identical, to placements, which are actually part of the information embedded into ad tags. Here is an example JavaScript ad tag:

<SCRIPT language='JavaScript1.1' src=";abr=!ie;sz=250x250;ord=[timestamp]?" ></SCRIPT>

ad unit

An Ad or set of ads displayed as a result of a piece of  ad code executing. A single unit of ad space.

ad targeting

The practice of serving an ad to the appropriate audience based on data. Ad targeting can involve demographic, geographical, behavioral or psychographic data.


The ability to dynamically serve targeted ads to the household or user based on deterministic identifiers, allowing brands to define and serve their message to the best qualified audience, wherever and whenever they're watching.

addressable TV

The ability to dynamically serve targeted ads to specific TV households based on deterministic identifiers, allowing brands to define and serve their message to the best qualified audience, wherever and whenever they're watching content on TV, connected TV, or //STB.

addressable video

The ability to dynamically serve targeted ads to the HH or user based on deterministic identifiers, allowing brands to define and serve their message to the best qualified audience, where ever and whenever they're watching video content on any device.

advanced TV

Any television content that has evolved beyond traditional, linear television delivery models. This umbrella term is inclusive of the following:

  • Connected TV (CTV): A TV that is connected to the Internet via an external (for example, streaming devices and gaming consoles) or internal device (for example, a smart television)
  • Smart TV: A subset of Connected TV.
  • Addressable TV: The ability to serve targeted ads to the HH or user based on deterministic identifiers, allowing brands to define and serve their message to the best qualified audience, where ever and whenever they're watching.
  • OTT: (over-the-top) TV-like video content delivered over the internet, bypassing traditional TV infrastructure.
  • Interactive TV (iTV): The catch-all term for adding a viewer engagement piece to television, which may include interactive content, interactive advertising or ichannels. This can be delivered in a variety of ways, including through the first- and second-screen.


 The company paying for the advertisement.


See ad agency.


A list of television networks, site domains, or apps that a buyer explicitly wants to buy ad space on.


An API, or application programming interface, is a programming method used to interact with software, applications, or tools. APIs provide a simplified querying language that allows consumers or developers to access underlying databases and hardware without disrupting stability or reliability, and without knowledge of underlying programming languages. They may be based on a variety of programming languages and models, but the types of APIs used by consumers to interact with Web-based software or apps are often known as SOAP or REST services, which consist of a set of specifications for remote calls that enable consumers to interact with data and systems without the risk of disrupting their function. For example, Xandr uses a RESTful API to facilitate interaction with its Web-based software.


The process of identifying a set of user actions across screens and touch points that contribute in some manner to a desired outcome, and then assigning value to each of these events. Attribution offers advertisers the opportunity to understand how media can drive sales, awareness, purchase intent, and other measurable KPIs.

audience deficit unit (ADU)

Additional, no charge audience units that are added to make up for shortfall/underdelivery on a paid schedule. Can be applied to later campaigns instead, sometimes.

audience graph

An audience graph combines the notion of a Customer Profile with an ID Graph, which allows companies to understand both who their customers are as well as what they are doing.

autoplay video ad

A video ad or an ad linked with video content that initiates ‘‘play’’ without user interaction or without an explicit action to start the video (essentially automatically starting without a ‘‘play’’ button being clicked by the user).

audible and viewable on complete (AVOC)

The percentage of measurable impressions that were played, and were audible and visible when the video has reached the deemed completion mark. The video could be deemed complete at the end of the video or after a certain number of pre-determined seconds.

automated content recognition (ACR)

ACR is an opt-in identification technology embedded in a device that allows content to be recognized by video, audio or watermark cues and matched back to a data base for verification. This technology can recognize content regardless of its distribution source (i.e. OTT, linear, etc.). Marketers use this information to understand when a consumer has seen their ads.

average audience (AA)

The estimated average audience of a program during a time increment of its duration.

average audience projection / impression

The rating expressed in numeric rather than percentage form.

average hours of viewing

HUT/PVT converted to the average hours of viewing per home or per person. The two measurements are simply different ways to express the same statistic. Average Hours = Duration of the period x HUT%

average frequency

The average number of times a household or person viewed a given television program, station or commercial during a specific time period.

advertising video on demand (AVOD)

AVOD is an OTT service that provides free or reduced-cost video on demand that is displayed with various types of advertising (pre-roll, mid-roll, post-roll, or more creative types such as pause ads). As an alternative to SVOD, AVOD offers free streaming with advertising. Services include traditional broadcasters’ BVOD players (eg. ITV Player) and a new wave of digital-native AVODs (e.g. Tubi).


Inventory that is not pre-sold, also known as remnant inventory. Can also refer to one ad network filling unsold inventory for another ad network.

back-to-back ads

Playing out the same ad repeatedly kills effectiveness. Back-to-back play-out control limits the risk of repeat.

A basic image or flash display ad, rather than a rich media unit.

behavioral data

Information collected from a users' online actions, for example, things they’ve searched for in the past and types of website they frequent. Advertisers sometimes use this type of data in their campaigns to match relevant users with their offers, in a privacy and data compliant way.


A bidder is a piece of technology that uses proprietary code and algorithms to analyze bid requests and respond with bids and creatives in real-time auctions. For example, Xandr hosts a bidder that represents Xandr UI clients' buy-side settings.

bidding strategy

A bidding strategy is the way a buyer calculates a bid in an ad auction. It can mean bidding a flat CPM or bidding a variable price based on past clickthrough or conversion rates.

bid request

A request sent to a bidder that asks it to return a bid for a given impression. Bid requests include data points about the user and the impression being sold.

bitrate or bit rate

  • Encoded bit rate: The number of bits (or amount of data) per second that has been used to store a media signal. In audio, this usually is presented in kilobits per second (or kb/s or kbps), while for high-quality video, this might be presented in megabits per second (or Mbps, or Mb/s). For example, the music you buy on iTunes is 256 kilobits per second, meaning there are 256 kilobits of data stored in every second of a song, and an HD video file might be encoded at 2.0 megabits per second, meaning there are two megabits of data. The encoded bit rate is the one used for business requirements as it represents a strong signal of fidelity.
  • Available bit rate: The instantaneous delivery rate of data in bits per second (bps), kilobits per second (kbps), megabits per second (mbps), etc. from the source server to destination device through one or many digital networks. The slowest portion of the network path determines the end-to-end maximum bitrate of the delivered stream. Some media content such as audio streams may use less than the maximum available bandwidth. HTTS Live Streaming (HLS) is a variable bitrate protocol for delivering video content. HLS starts the stream at a low bitrate which provides low video resolution and increases the bitrate and video resolution as the network conditions permit. The available bit rate is used for technical purposes as it represents how much data can be passed from the ad server to the client for an ad to deliver without jitter.


A list of television networks, site domains, or apps that a buyer doesn't want to buy ad space on.


A company's product line and the image and reputation of that line. Many stakeholders in the ad tech industry have guidelines or requirements for the use of branding in creatives. Can also refer to a specific company name, such as Coke, Target, Honda, and so on.

broadcast networks

Video content that is aired on ABC, NBC, CBS, FOX or the CW.

broadcast VOD

Programming made available by broadcast networks, through their own access platforms, usually following live transmission.

cable networks

Video content that is aired on networks outside of ABC, NBC, CBS, FOX or the CW and are viewed via linear pay TV or OTT.


In advertising, a campaign is a set of media that has a shared themes and ideas to market a specific brand, product, or concept. Most campaigns also include criteria such as a specific start and end date, daily or overall budgets, frequency restrictions, and targeting based on user or inventory data. Ad campaigns run on a variety of places including linear television, connected TV, online and apps.


Content delivery network. A CDN delivers static content, such as creative image or flash files. Usually, CDN providers have servers across the globe configured to deliver content as quickly as possible, which is why it's typical for ad servers to rely on them.

click log

A server-side log of predefined information gathered when when a user clicks on an ad.

click-through rate

See CTR.

click URL

If a publisher is being paid on a CPC basis and wants to track clicks, they can provide click-tracking URL where it is possible to ping them each time a user clicks on an ad. Click URLs can also be used by to record clicks en route to a landing page. See also publisher click-tracking.

competitive separation

Ensures a publisher’s ad pod does not include conflicting brands or categories, thereby reducing competition and consumer ad fatigue, and increasing the value of the spot.


In general, a computing cloud is a networked group of servers accessible through remote means. In ad tech, this usually refers refers to cloud computing infrastructure on which an ad platform of some kind runs. Data or processes existing within such a network is sometimes said to be "in the cloud". 

connected audio

An audio device that is connected to the internet via an external device (For example: a smart speaker or a bluetooth speaker). An external audio device plays media content by streaming from the internet or local storage. Connected audio is only available when your ad type is "Audio". Smart streaming audio devices include Google Home Max, Amazon Echo, Apple HomePod, etc.

connected TV (CTV)

A TV that is connected to the Internet via an external (for example: streaming devices and gaming consoles) or internal device (for example: a smart television). CTV devices are the hardware used to access content over the top. They include dedicated streaming dongles (eg. Roku, Apple TV, Chromecast, Fire TV), games consoles like Xbox and Playstation and integrated smart TV sets.

container tag

See tag container.

contextual data

Information on the contents of the webpage that a user is viewing upon ad call, usually used for ad targeting. For example, if the user is viewing a newspaper article about travel, an airline may wish to display on that page. This is distinct from user data. See also semantic targeting.

contextual targeting

Buying ads against the TV show, rather than the audience, based on certain descriptive metadata like genre, mood or subject matter.


When a user signs up, makes a purchase, or performs some other desired action in response to an ad. Also called an acquisition or action, especially to distinguish conversions/acquisitions from clicks in payment methods (CPC vs. CPA).

conversion attribution

See attribution.

conversion funnel

This describes the journey a consumer takes as a sum of experiences when interacting with your company and brand. Instead of looking at just part of a transaction or experience, the customer funnel looks at the full experience from awareness to consideration to intent and finally conversion or purchase.

conversion pixel

A pixel that fires when a user "converts" by clicking on a ad, registering, making a purchase, or completing another action. Advertisers can place conversion pixels on a landing page, registration page, checkout pages, or elsewhere to track conversions.

converged buying

As traditional TV evolves, CTV grows and media continue to fragment, the industry wants to combine buying and selling activities across the ecosystem, to enable unified planning, buying and measurement across media channels.

A parcel of text sent by a server to the cookie file in a browser and then sent back unchanged by the client each time it accesses that server. HTTP cookies are used for authenticating, session tracking, and storing information about specific users, such as site preferences or buying habits. Advertisers often use cookies to track the number and frequency of advertisements that have been shown. See also first-party cookies and third-party cookies.

cost per viewable impression

A pricing model where the advertiser only pays for video ad impressions that are considered viewable based upon MRC and IAB viewability guidelines. Typically sold at 1000 impressions.

cost plus

A payment model in which advertisers agree to pay the cost of media plus an additional CPM or % profit margin on top.


The percent of TV households that could receive a program. It’s the ability to view, not actual viewing.

coverage area rating %

Average Audience in percent of homes able to receive an individual cable network or specialty channel. The number of stations transmitting the program.

Coverage Area Rating % = Average Audience % ÷ Coverage Area Universe Estimate


Cost per action/acquisition. A payment model in which advertisers pay for every action, such as a sale or registration, completed as a result of a visitor clicking on their advertisement. Note that an "acquisition" is the same as a "conversion".


Cost per install. A payment model in which mobile advertisers pay each time a user installs their app.


Cost per click. A payment model in which advertisers pay each time a user clicks on their advertisement.


Cost per completed View. The price an advertiser pays every time a video ad runs through to completion. Rather than paying for all impressions, some of which may have been stopped before completion, an advertiser only pays for ads that finished (CPCV = Cost ÷ Completed Views).


Cost per mille, or thousand (mille = thousand in Latin). A pricing model in which advertisers pay for every 1000 impressions of their advertisement served. This is the standard basic pricing model for online advertising. See also CPC and CPA.


Cost per rating point. The cost to deliver a single rating point. CPP = Average Unit Cost/Rating % or Total Schedule Cost/GRPs.


Cost per view. A pricing model where the advertiser only pays for a video start. Typically sold at 1000 impressions.


Renamed. See vCPM.


An advertising unit created in accordance with publisher specifications and guidelines, for the purpose of communicating a marketing message to that publisher’s audience. A creative can include images, animation, video, interactive experiences or more.

creative tag

Similar to an ad tag, this is a snippet of code that gives the location of the creative, which is usually a content delivery network (CDN) or an ad server.

cross-screen addressable

Ability to reach the same audiences across addressable TV and digital touch-points within STB, CTV, desktop and mobile.

cross-screen measurement

Tracking and measurement of video metrics across Mobile/Tablet/Out-of-Home/Television/Advanced TV/Desktop.


Comma separated values. A data file structured in a table form with fields separated by commas. This is one file format used to transmit multiple creative tags during bulk sending.


Click-through rate - the rate or frequency at which users click through to a landing page from an ad.


See connected TV

Curated Deal

Aggregation of targetable supply via a customizable, multi-publisher inventory packaging solution. Curated deals launch campaigns against a single Deal ID, so no wasted time and resources are dedicated towards publisher sourcing and deal creation.

Customer Profile

Customer profiles are a collection of demo, intent and behavioral data assigned to specific individuals or households.



The Digital Advertising Alliance. An online advertising industry association, made up of many other organizations, and dedicated to self-regulation. Possibly best known for the Advertising Option Icon. Read more on the DAA's website.

daisy chain

When the linking of several ad tags, usually from different exchanges, ad servers, or ad networks, creates a "waterfall"  – or "daisy chain" – of impressions passing from tag to tag. If no creative is found via the demand available to Ad Tag 1, the impression can be passed to Ad Tag 2, Ad Tag 3, and Ad Tag 4 to see if demand is available there, and so on until a creative is found and served.

data-driven linear

The ability to use different data sets including demographics, interests, and viewing behavior to optimize a linear TV schedule that uses specific networks and day parts to better reach an advertiser's audience.

data management platform

In ad tech, a data management platform (DMP) is a centralized system for gathering first-party data, integrating with third-party data, and applying this data to one's advertising strategy. A DMP may offer the following features: estimating the likely reach for a user segment, measuring the lift from using data, acting as a financial clearing house between data buyers and sellers, and assisting publishers in monetizing data on their users. DMPs most commonly work with user data but may also work with contextual data, or other types of data.

data provider

A business that collects data about users, companies and brands and makes the information available in a safe and data compliant way for advertisers to better understand and serve media to their audiences.


The automated process by which an ad server, ad platform, or exchange literally decides where, how, and to whom to serve an ad. This can be based on an auction prioritizing certain kinds of online ad space, prioritizing advertisers based on relationships and prior agreements, or other methods.


Sometimes known as "de-duping" – means removing duplicate entries or events in a data set. Effective programmatic buying is dependent on getting accurate and useful data sets, and deduplication is often a step in that process. For example, if a user clicks twice on the same creative but these two actions are only linked to a single conversion, it's possible to de-dupe the associated data set to prevent it from counting second clicks.

default creative/reserve creative

A default creative is a creative that runs as a backup in an open Internet ad space, in the case that no other creatives are available. A default creative can be a literal creative, say an in-house ad, or it can be a redirect in the form of a third-party ad tag to a third-party ad server. A default creative may also be called a "reserve creative."

default tag

If no impression can be found for an ad opportunity, a default tag may be served. The tag is passed to a third-party ad server to see if demand can be found there (this happens in the case of daisy chaining) or to simply pull a creative from that server. Sometimes called a passback.


Advertising demand, or the desire to buy ad space and display creatives.

demand side platform (DSP)

Technology that allows advertisers to buy impressions across a range of publisher sites, but targeted to specific users based on information including location and previous browsing behavior. Publishers make ad impressions available through programmatic marketplaces and DSPs automatically decide which impressions make the most sense for an advertiser to buy.

deterministic data

Known data that identifies a consumer via a 1:1 match of two or more data sets based on unique identifiers.

deterministic ID

Audience profiles built from verified known subscriber or user data, authenticated from TV services.

device-Level targeting

More-granular targeting that identifies, profiles and reaches a specific device, whether it is a smart TV, mobile phone or desktop computer.

digital ad rating (DAR)

DAR is a tag created by Nielsen that is placed on a web page or within a CTV app that provides cookie based audience demographic reach measurement.

digital out-of-home advertising


direct response

A term applied to marketing or advertising that is designed to solicit a direct response which is specific and quantifiable. In online display advertising, examples of this can include clicking on an ad, making a purchase, signing up for a newsletter, and so on.

display advertising

Online advertising is often divided into "display" and "search." Display ads are images and search is text based. Display ads, sometimes referred to as banners, come in standardized ad sizes, and can include text, logos, pictures, or rich media.

direct marketing association (DMA)

An independent nonprofit organization of "data-driven marketers" whose stated mission is to "advance and protect responsible data-driven marketing". For more information, see the DMA website

direct media buy

A pre-brokered agreement between an advertiser and publisher to deliver a certain amount of specific inventory for a preset cost.

direct response

A term applied to marketing or advertising that is designed to solicit a direct response which is specific and quantifiable. In online display advertising, examples of this can include clicking on an ad, making a purchase, signing up for a newsletter, and so on.

direct marketing association (DMA) online behavioral advertising (OBA) compliance

The Direct Marketing Association has been heavily involved in creating guidelines for online behavioral advertising (OBA), or advertising to people surfing the Internet based on their past browsing history. For more information, see the DMA Website.


See data management platform.


Digital out-of-home advertising is dynamic media experienced outside of the home, such as on digital billboards and other signage.


See direct response.


See demand side platform.

duration averaging

Averaging programs together by weighting according to the length of each program.

dynamic ad insertion (DAI)

Technology that allows advertisers to swap out ad creatives in video on live and on demand content based on who the ad is intended for. This allows ads to be served to unique and targeted individuals rather than TV broadcast commercials where all viewers are served the same ad. It enhances the ability to swap out an ad in a TV show, based on audience targeting signals or buyer strategy. It was originated in VOD, but now emerging in live digital linear streams.

dynamic creative

Many advertisers wish to show different ads to different customers; for example, an advertiser might wish to show rain gear to people who live in rainy climates and sunblock to those who live in sunny climates. Dynamic creatives refers to having a few different creatives and choosing the most appropriate one for the user through some automated means such as audience segmentation or based on frequency and recency. Many platforms have rules about how much creatives can vary within the same placement – for example, there may be limitations on rotating brands.

dynamic pricing

Purchase pricing for an ad impression that is determined via real-time bidding (RTB) rather than a predetermined rate.


Effective Cost Per Acquisition. This is calculated by dividing your cost (or revenue) by the number of conversion events. Shows how much is spent in CPA when payouts are measured using another pricing model.  


Effective Cost Per Click. A translation from CPM, CPC, CPA, and other pricing models so that they can be compared. Shows how much is spent in CPC when payouts are measured using another pricing model.


Effective Cost Per Thousand. A translation from CPM, CPC, CPA , and any other pricing models so they can be compared. Shows how much is spent in CPM when payouts are measured using another pricing model.

engagement metrics

In advertising, engagement metrics are the metrics used to measure consumers' engagement with the ads they encounter. Engagement metrics are used by media buyers to gauge the effectiveness of their advertising. This is most easily done by direct marketers who use CPA buying strategies, but there are a variety of other ways to measure the impact of ads via engagement. Some possible engagement metrics include whether a user has watched an entire video ad, if a user hovers over a creative with a mouse, and whether a user has clicked on an ad. More generally, the term engagement metrics may also be applied to a range of online behaviors, such as how long a visitor spends on a website.


See ad exchange.

expandable ad

Rich media creatives that can be enlarged beyond the initial dimensions of the placements they fill on web pages.

first-party cookies

Cookies that use the domain of the website a user is currently on. For example, if you visit and the domain of the cookie is, then this is a first-party cookie. First-party cookies are usually used for login, user experience, and retargeting purposes. See also third-party cookies.

first-party data

First-party data is information collected directly and stored by publishers, retailers, brands and other types of companies about their audiences or customers. 

first touch

An attribution model in which gives credit for the first impression a user saw. This may be used as an alternative to the last view/last click model, which gives credit for the last viewed or clicked ad.


The lifetime of a campaign, from its start date to its end date. A campaign can also have no flight dates and continue indefinitely. A campaign that is active is said to be "in flight".


How often an ad is shown in a certain period, such as a single browsing session, a 24 hour period or a flight. Advertisers often want to manage frequency to avoid showing an ad to the same user too often, also known as overexposure. See also recency.

frequency capping

The act of limiting, or "capping" how often a particular creative can be served to a user. For example, an advertiser might use frequency capping to ensure that an ad could be shown to the same user no more than three times per 24 hours. See also recency capping. It allows brands to guard against agitating viewers with repeat exposures, by specifying a maximum threshold for playback.

frequency distribution

Number or percentage of households or persons that are exposed to a given program, station, or commercial on time, two times, three times etc.

full episode player (FEP)

A placement on a web page that has the ability to play videos that are TV-length (typically 30-60 minutes, sometimes more), and often includes multiple ad breaks throughout the streaming video content.

gross average audience (GAA)

The estimate which reflects the sum of all tuning and viewing minutes to a program. Tuning and viewing to the same minute of a program (or its repeat telecast) are counted each time.

gross impressions (IMP)

The GRPs expressed in numeric rather than percent form. Impressions = GRPs x Universe.

gross rating point (GRP)

A term used to measure the size of an audience reached by a specific media vehicle or schedule. It is used to measure the exposure to one or more programs or commercials, without regard to multiple exposures of the same advertising to individuals. For example, an advertisement that is aired/served 5 times reaching 50% of the target audience each time it is aired would have a GRP of 250 (5 × 50%). GRP values are typically used by media buyers to compare the advertising strength of various media vehicles.

guaranteed inventory

Inventory consisting of impressions sold ahead of time, rather than in a real-time auction via real-time bidding. Called guaranteed because the publisher signs a contract with an agency committing to deliver the specified impressions in exchange for an agreed-upon sum. If the guarantee is not met, the agency will often request a “make-good,” usually in the form of a credit. See also premium inventory.

household-level targeting

Two households may watch the same show via CTV but may be served different ads based on various identifiers.

hybrid broadcast-broadband TV (HbbTV) - An international consortium and standard aimed at combining digital terrestrial broadcast and broadband delivery of programming.

hybrid SVOD/AVOD - Services that combine subscription and ad support tiers — for example, offering a lower subscription with ad support or a premium, ad-free experience.

ID synching

See  user ID mapping.

identity graph

An Identity Graph, or ID Graph, is a database that stores all identifiers that correlate with individual customers. These identifiers could be anything from usernames to address, email, phone, cookies, device IDs, IP address and even offline identifiers. It is third-party sources of viewer data against which to buy, often compiled from combining multiple viewer signals, in lieu of on-device identifiers.

identifier for advertisers (IFA)

A random device identifier assigned by Apple to a user's device. Advertisers use this to track data so they can deliver customized advertising. It provides device-level identification whilst giving users control over information accessed by apps.


An HTML iframe tag tells the browser to open a mini browser window of a specified size inside the current window. This way the ad content cannot expand beyond the size specified and "take over" the screen.


A creative served to a single user at a single point in time. Sometimes called an "imp".

in-banner video

In-banner video is a type of creative played in a standard banner rather than in a video player. Any banner placement may accommodate an in-banner video creative, if allowed by the publisher.

in-commerical overlays

A linear TV advertising format that is displayed with a TV commercial. This is displayed as a banner overlay that appears 5 seconds after the ad begins and disappears 5 seconds before it ends. This is clickable to alternate options such as recording a program, requesting information about the advertiser, etc..

in-stream video ad

A video ad that is played before, during or after streaming video content (Pre-roll, Mid-roll, Post-roll). These ads cannot typically be stopped from being played (particularly with pre-roll) but can sometimes be skipped. In-Stream Video Ads can be played inside short or long-form video and are encompassed within the content streaming experience.

in-stream video

In-stream video is a type of creative played in video players on Web pages. This creative type uses VAST XML to ensure proper rendering in players and are shown before, in the middle of, or after other video content.


Also called a virtual machine, virtual operating system, or virtual server, an instance is an individual guest operating system that runs on top of a virtualization layer on top of a physical server. Instances are the building blocks of cloud computing.

interactive advertising bureau (IAB)

An online ad industry association focused on the growth of the interactive advertising marketplace whose stated goal is to educate "marketers, agencies, media companies and the wider business community about the value of interactive advertising". Read more at the IAB's website.

interactive channel

A linear TV channel that allows for interactivity and clickable advertising by using the selective buttons and arrows on their remote control. These channels have one brand advertiser that sponsors the interactive ad.

interactive TV (iTV)

The catch-all term for adding a viewer engagement piece to television. This can include both interactive content and advertising, and can be delivered in a variety of ways, including through the first- and second-screen.

interactive video

A type of digital video creative that can take user input to perform some enhanced actions through elements integrated above and beyond the standard video playback controls (i.e., play, pause, rewind, and mute). These interactions can include varied calls-to-actions, forms, polls/surveys, links, chapter menus and hot-spots that may affect story progression of the video content and/or drill down on specific parts of the content itself. The goal of the creative is to give the user various options to engage with the message beyond viewing the video.

interstitial ad

An ad that displays as a user navigates from one web page to the next. The ad fills the browser window after the user leaves the initial page, but before the target page displays on the user’s screen.

internet protocol TV (IPTV)

Whilst all of these methods involve IP, IPTV often refers to programming delivered over broadband via an internet service provider’s own TV service, rather than OTT third parties. Operating in a closed circuit means they cannot communicate with third-party ad servers like other CTV services, adding operational complexity.


The total number of ad views or impressions that are available to sell over a given period of time. Publishers sell ad inventory.


JavaScript Object Notation is a lightweight data-interchange format based on a subset of JavaScript. JSON is a programming language often used for APIs. It is a language-independent text format that uses conventions from the C-family, including C, C++, C#, Java, JavaScript, Perl, and Python. A JSON object looks something like this:

   "glossary": {
      "entry": "CPM",
      "definition":"See Cost Per Mille" 

landing page

The page to which a user is directed after clicking on an ad. For example, if a user clicks on a Cheese of the Month ad, they may be directed to, or to or some other landing page chosen by the advertiser. The landing page may be slightly different from the click URL.

last click

A type of attribution model that pays out on the last impression that was clicked on by the user. This may be used as an alternative to the first touch model, which gives credit for the first impression a user saw.

last view

A type of attribution model that pays out on the last impression that was viewed by the user. This may be used as an alternative to the first touch model, which gives credit for the first impression a user saw.


The percent increase in performance (measured in ROI, CPC, CPA, etc.) that can be attributed to advertising (or some other marketing endeavour).

linear TV

TV delivered in a live broadcast, non-time-shifted or DVR'd manner.

live streaming video

Video content streamed digitally in real time as the event or program is aired by the network. Content can be streamed on mobile devices, computers or connected TVs.

location data

Anonymous, user-level data collected from a mobile device and that provides anonymous information about its current position in space. Location data is typically used to provide foot-traffic attribution, audience segments for targeting, offline analytics based on the understanding of consumer offline patterns. It can be 1st, 2nd or 3rd party data.


Ad inventory with relatively low exposure or limited users, such as a personal blog with a very low number of followers, or numerous less desirable users, such as people who are very young, have minimal disposable income, or other factors that would make them unlikely consumers of a product or service. The long tail can be difficult to monetize.

long-form video

Video content that always has a content arc with a beginning, middle, and end and that, in its entirety typically lasts longer than 8 minutes (i.e., movies and original series). If the content is ad supported, it typically contains breaks (mid-roll). This is different than commercial videos, which typically put the product upfront and run under one minute.

lookalike model

Used to build larger audiences from smaller segments to create reach for advertisers. The larger audience reflects the benchmark characteristics of the original audience. In the context of marketing, lookalike modelling can be used to reach new prospects that look like a marketer’s best customers.

lookback window

An amount of time taken into account when collecting data to be used for attributing conversions, a bid optimization model, or anything else. Common lookback windows are a day, 14 days, 30 days, etc.


mobile advertiser ID

A mobile advertiser ID (MAID) is a sequence of alphanumeric characters assigned to a mobile phone or tablet by the device operating system (iOS or Android).


Generally a large advertiser that manages at least some of its own advertising. Also called a direct marketer.


Created when buyers and sellers come together. The combination of inventory (and data) that sellers of media make available to buyers of media to purchase. Platforms can support multiple marketplaces and media offerings, and conversely a marketplace can exist without a platform as well.

media plan

A holistic view of a given advertiser's media buys. Often managed by a media agency.


The process of sending bid requests to ad buyers outside of the Xandr exchange via a client or server side redirection, with passbacks in case the buyer doesn’t fill the impression. Mediation enables access to additional ad networks to maximize fill rates. There are two main categories of mediation: web mediation and mobile mediation.

mediated ad network

An ad network  that sits outside of RTB auctions for online inventory, but participates in auctions alongside real-time bidders and direct advertisers by setting up proxy “bids” that  represent that network’s demand.


Metadata is data about data. Metadata can be used to do things like label creatives or ad inventory with information like brand, size, and other constraints or data. 

metro code

A geographic value that doesn't fall under the country/region/city/zip code hierarchy.

mobile device ID

A unique identifier for a mobile device. The device ID cannot be linked to personally identifiable information (PII). Different operating systems use different identifiers: IDFA (iOS), AAID (Android), and Windows Advertising ID (Windows).

mobile mediation

Mobile mediation typically involves server-to-server requests via two systems to determine if the buyer has an ad, or embedding an ad network’s SDK within your SDK to make calls to the buyer’s ad server.  


Mobile Rich Media Ad Interface Definitions (MRAID) is a common API (Application Programming Interface) for mobile rich media ads that will run in mobile apps.

multi-channel attribution

The ability to follow known audience viewing behaviour after the fact—for example, using smartphone location data or website analytics to correlate outcomes back to ad exposure.

multi-channel video programming distributor (MVPD)

A service provider that delivers video programming services, usually for a subscription fee (pay television). Usually includes cable, satellite, and telecommunications service providers.

Network Advertising Initiative (NAI)

An online advertising industry association focused on consumer education about online behavioral advertising (OBA). Read more at the NAI website.

native advertising

A form of paid media where the ad experience follows the natural form and function of the user experience in which it is placed. These paid ads aspire to be so cohesive with the page content, assimilated into the design, and consistent with the platform behavior that the viewer simply feels that they belong.


A network traditionally refers to a cable, broadcast or premium programming channel on TV. Generally refers to an ad network

nonexclusive inventory

Inventory for which a given ad trafficker can't be certain where they are in the ad call daisy chain. They may be first or the ad call may have already passed through another platform as part of a daisy chain.


See owned and operated.

offline data

Data collected in offline environments, such as vehicle registrations, shipping, loyalty card transactions.

omni-channel audience reach

Advertisers can track engagement across all digital devices, including CTV devices, to gain campaign-wide insights.

online behavioral advertising (OBA)

Advertising to people surfing the Internet based on their past browsing behaviors. See also DMA OBA compliance.

online data

Data collected from online operations. Data may be collected via cookie, online declared data, registration/login, product data, preference data.

open marketplace (open exchange)

An auction in which several media owners offer up their ad inventory for sale to a number of buyers, who all compete for the opportunity to place their ads within the available inventory.


The process of using historical data to adjust an approach to buying a piece of inventory. In programmatic buying, this information will frequently be used to either alter the bid price for a piece of inventory or determine if a buyer is willing to bid on a piece of inventory at all.

OTT device

A device that can connect to a TV (or functionality within the TV itself) to facilitate the delivery of OTT (internet-based) video content. These devices include media streaming devices (i.e Ruku, Apple TV, Chromecast), Smart TV’s and gaming consoles. Xandr speaks to this definition interchangeably with connected TV and connected TV device.

outstream video

A type of video ad embedded within an article or other body of web content, mostly set to auto-play when the reader reaches the part of the page that contains the ad.

out-stream video ad

A form of video advertising that takes place outside of In-Stream Video content. One type of out-stream video is in-feed video ads which are found in content, social, or product feeds. Another type of outstream video ad is in-article video ads that are served between text.

over the top (OTT)

OTT (Over the Top) video is TV-like video content delivered over the internet, bypassing traditional TV infrastructure. Previously, TV was delivered via airwaves, cable or satellite to receivers or set-top boxes. Increasingly, the internet is the access mechanism through which programming is obtained. Services like Netflix, Pluto and Hulu deliver “over the top” of the internet. Can include online video distributors like Hulu and Amazon Prime Video, plus virtual multi-platform video distributors (vMVPDs) like Sling TV and fuboTV.

owned and operated

A type of publisher that both owns and operates its inventory sources. Different from a managed publisher, which does not own or operate its inventory sources, but has a financial relationship with those who do.


The redirecting of an impression back to an ad server  when no acceptable bid is received from a mediated bid, in order to allow the next highest bidder a chance to win the impression. See also default tag.

personally identifiable information (PII)

Information included in any data set that allows users of the data to resolve the real-world identity of the data subject. 

Premium entertainment satellite

PESAT is the delivery of premium channels (HBO, STARZ, etc.) over satellites.

PHP session ID

A PHP session allows you to store user information on a server for later use. However, session information is temporary and will be deleted after the user has left a website. Sessions work by creating a unique ID (UID) for each visitor and storing variables based on this UID. The UID is either stored in a cookie or is propagated in the URL.


This term usually refers specifically to a piggybacked pixel. When pixel A has pixel B piggybacked on to it, then the firing of pixel A causes the firing of pixel B. This second firing can either be via a redirect or a server-side firing. Piggyback pixels may be used for tracking conversions in secondary systems. 


See personally identifiable information


A pixel is a way to track user data. Originally, all pixels were literally snippets of code that called for a 1X1 transparent pixel to be delivered to a webpage by a third-party server. Nowadays, pixels may either be literal pixels or be javascript based. When the pixel loads, the third-party server can record information such as the IP address of the user's computer, URL of the page, and time the page was viewed. See also conversion pixel and segment pixel.


A term describing the object that represents a piece of inventory. Often refers to the location an ad will be shown.


Enterprise technology that enables buyers and sellers to more easily transact advertising inventory.

pop ad

An ad that displays in a secondary browser window. Pop-up ads display in front of the initial browser window, while pop-under ads display behind it.


An ad that displays in a secondary browser window directly behind the initial browser window. See also pop-up.


An ad that displays in a secondary browser window directly in front of the initial browser window. See also pop-under.


Profit per thousand, or mille impressions ( mille  = thousand in Latin). A useful measurement for ad networks, whose goal is to buy cheaper inventory and sell it at higher prices.

premium inventory

The term "premium" can be used in different ways, but it most commonly refers to publisher inventory that is sold through direct channels in advance – in other words, guaranteed inventory. Often premium inventory is from a site's home page, or has some other elevated level of desirability. See also remnant inventory.

premnant inventory

A portmanteau word of premium + remnant. "remnant inventory," or non-guaranteed inventory has an unnecessarily negative connotation when this inventory might be first-rate.

private marketplace

Invitation-only marketplaces where premium publishers make their inventory and audience available to select buyers, often times transacted through the use of Deal IDs.

probabilistic data

Inferred or modelled data that identifies an audience that has a high probability of being a particular consumer.

probabilistic ID

Inferred audience profiles modelled based on previous behaviour and statistical analysis, risking imprecision when compared with deterministic IDs.


The automated buying and selling of inventory.

programmatic buying

Buying through automated means, for example, by setting up a campaign in an RTB exchange or other automated system. This is opposed to more manual buys where you are in contact with a sales team, or other "offline" mechanism.


Public service announcement. On many ad serving platforms, a PSA will serve if there are no acceptable bids on a piece of inventory and the publisher does not have a default creative set.


A source of inventory. Publishers are generally either managed or owned and operated. An owned and operated publisher receives 100% of the profit for impressions sold. This is opposed to a managed publisher: a publisher that does not own its inventory but has a financial relationship with those who do.

publisher click-tracking

When a publisher keeps track of clicks on their ads. If a publisher is being paid on a CPC basis and wants to track clicks, they can provide click-tracking URL where it is possible to ping them each time a user clicks on an ad.

query string

A way to pass data to a web application as part of a URL. For example, at Xandr a buyer can target ads based on the information in the querystring. The query string comes after a "?" in the URL, for example:

rating %

The estimate of the size of television audience relative to the total universe, expressed as a percentage. The estimated percent of all TV households or persons tuned to a specific station.


The number of different or unduplicated homes/people that are exposed to a television program or commercial at least once across a stated period of time. Also called the cumulative (cume) or unduplicated audience. During the course of the schedule shown in the illustration above, seven different households were exposed to the commercial at least once. Since each home represents 10% of the universe, this makes the reach or cume 70%.

real-time advertising

In real-time advertising, ads are shown as the result of real-time bidding auctions.

real-time auction

See real-time bidding.

real-time bidding (RTB)

Real-time Bidding (RTB) is a way of transacting media that allows an individual ad impression to be put up for bid in real-time.

recency capping

A way to limit the showing of an ad over time. For example, an advertiser might want to avoid showing an ad to a specific user ID more than once per hour.


Targeting users who have performed an action in the past, who may therefore be more likely to perform the same or a similar task in the future. For example, an advertiser might wish to put a segment pixel on their website and then target users who have visited the website in the past because they are more likely to make a purchase.

remnant inventory

Inventory sold after premium inventory has been pre-sold by a direct salesforce. Remnant inventory is sometimes synonymous with real-time inventory, and is often the target of programmatic buying. Because remnant has an unnecessarily negative connotation, other terms that have been experimented with are "premnant" (premium + remnant} or "secondary premium." Also sometimes called "tier 2" or "class 2."


In ad tech, reporting data for both buyers and sellers, such as audiences reached, effective cost, money spent, impressions seen, impressions sold, and revenue earned.


In general, the term "request" can refer to any attempt by one's browser to retrieve a page, including page elements such as ads, from a server on the Internet. In ad tech it usually applies to a request for a creative or ad tag.

reserve creative

See default creative.

reserve price

The lowest price at which a bidder or member will sell an impression.


Representational State Transfer. A type of API protocol that operates on POST, GET, PUT, and DELETE commands.


Targeting users who have performed an action in the past, who may therefore be more likely to perform the same or a similar task in the future. For example, an advertiser might wish to put a segment pixel on their website and then target users who have visited the website in the past because they are more likely to make a purchase.

return path data (RPD)

TV tuning data that comes from set-top boxes in cable and satellite subscribers’ homes. It can include information like the programs subscribers watch, when they watch them and where the subscriber households are located. This data helps enable audience measurement and addressable advertising capabilities.

rich media

Ads with which users can interact (as opposed to solely animation) in a web page format that are more elaborate than the usual banner ad. Often has non-standard characteristics such larger than ~40k, out-of-banner (OOB) behavior, features like "post to Facebook," plays video within a banner, or in-creative metrics collection. Expandable creatives are examples of rich media creatives.  

rising stars

A set of interactive rich media creative types defined by the Interactive Advertising Bureau (IAB). They include Billboard, Filmstrip, Slider, Portrait, Pushdown, and Sidekick. There is also a set of Mobile Rising Star ad units, which include Filmstrip, Pull, Adhesion Banner, Full Page Flex, and Slider. See examples at the IAB website.


Return on investment. Literally, how much profit is made when money is invested. ROI can also be an idiom for whether or how much a given action or risk pays off, both in ad trading and business in general.


Run of exchange. A term meaning inventory available for purchase on an ad exchange.


Run of network. A term meaning all inventory managed by a network.


Run of site. A term meaning all inventory available on a certain website.


Revenue per thousand, or mille impressions (mille = thousand in Latin). Related to the CPM bidding strategy

rotating creative

When a single ad tag is set to send one of several different creatives. Brand and other guidelines for creative acceptance may set limits on how much creatives may vary when associated to a single tag. For example, Xandr bans a single tag from showing ads for multiple brands. See also dynamic creative.


See real-time bidding


second party data

Second-party data is another company’s 1st party data. Second-party data is similar to first-party data, but it comes from a source other than your own audience. It could include data from many of the same sources first-party data comes from.

second price auction

An auction type in which the bidder who submitted the highest bid pays a price equal to the second-highest bid. Also known as a Vickrey auction. This auction type has been in use for over a century for the purchase and sale of a variety of goods and services and is based on game theory as applied to auction dynamics. It's a commonly used auction type in online ad trading.


Also called data segment or audience, a set of users who share one or more similar attributes.

segment data

See user data and contextual data.

segment pixel

A pixel that marks a user as belonging to a certain segment. For example, an advertiser might place a segment pixel on the homepage and mark all visitors to the homepage as "homepage visitors."

semantic targeting

In theory, semantic targeting means figuring out what the content on a webpage is really about and being able to place ads based on that content. For example, if a website says "sunny weather," is it about great beach vacations, or is it about skin cancer, and do you want to advertise flights to Florida on it or not? However, the term is often used by different people to mean slightly different things, and is often used to be synonymous with contextual targeting.

server-side ad insertion (SSAI)

Ads are delivered by publishers in the content stream itself, rather than called separately by viewing devices. Increases ad delivery speed, but reduces buyers’ visibility into campaign performance.

share (of audience)

The percent of Households Using Television (HUT) or Persons Viewing Television (PVT) which are tuned to a specific program or station at a specific time. Share = Rating/HUT.

short-form video ad

Advertising within video content that has a duration of less than 8 minutes.

skin creative

A creative that wraps, acts as a wallpaper, or otherwise surrounds page content with ad content.

skippable video ad

Video ads that allow viewers to skip after a predetermined number of seconds.


See supply side platform (SSP).

station count

The number of stations transmitting the program.

sticky video ad/adhesion ad

Digital video ads that are anchored to the bottom or top of the screen and follows the user as they scroll. They are allowed under the following guidance:

  1. Ad height MUST be less than 25% of the screen height.
  2. The ad MUST have a clear boundary to separate it from the content.
  3. The ad MUST cover the full width of the screen edge to edge.
  4. The ad MUST have a ‘close button’ above top right corner of the ad as defined in LEAN User Experience and Ad Content.


  • Technology that permits continuous audio and video delivered to a device from a remote website.
  • An Internet data transfer technique that allows the user to see and hear audio and video files. The host or source compresses, then “streams” small packets of information over the Internet to the user, who can access the content as it is received.

subscription video on-demand (SVOD)

A streaming service that consumers subscribe to for a fee and can access a catalogue of on-demand content. It facilitates a premium, ad-free experience for a monthly fee from services like Netflix, BritBox or Binge.


See inventory.

supply side platform (SSP)

Software used by publishers to aggregate, consolidate, and manage available demand sources and exchange inventory.


A snippet of HTML, generally either JavaScript or an IFRAME, that tells the browser to request some content from an ad server. Tag is often used to mean an ad tag but may also be a creative tag or some other kind of tag. A tag is provided by an ad server or exchange and placed in the webpage by a publisher.

tag container

Many advertisers and their media buyers use a number of tags for tracking impressions, clicks, conversions, and other data. Some use tag containers to manage these disparate pixel tags and make it easier to change them via a single source. When a page loads, the tag container code displays the code for all tags stored within the container.


See ad targeting.

technology providers

Third-party entities who may assist various parties involved in Internet advertising by providing access to bidders or other technology.

third party data

Third-party data is data that can be bought from outside sources that are not the original collectors of that data. Instead, large data aggregators pull data from various platforms and websites where it was generated. Essentially, aggregators pay publishers and other data owners for their 1st-party data, collect it into one large data set and sell it as 3rd-party data.

third-party cookies

Cookies with a different domain than the website a user is currently on. For example, if you visit, an Xandr cookie with the domain would be a third-party cookie. See also first-party cookies.


The date and time that a specific event – such as a click or conversion – occurred. Useful in reporting functions and attribution. For example, at Xandr, the timestamp format is YYYY-MM-DD HH:MM:SS. In this format, 12:15 PM on New Year's Day 2015 would be 2015-01-01 12:15:00.

trading desk

A buy-side trading entity housed within or working for advertising agencies. Also known as an agency trading desk or ATD. ATDs are usually the programmatic arms of holding companies. Independent trading desks, known as ITDs, are another kind of trading desk, and are usually outsourced managed services firms that run programmatic ad buys on behalf of advertisers or agencies.

TV everywhere

An online business model in which television broadcasters, particularly cable networks, allow their customers to access live and/or on-demand video content from their networks through internet-based services. The fee for such access is covered as part of their subscription to the service, via an MVPD. The viewers use credentials from their MVPD for authentication and access to the content either through the cable providers app/website or a network's own app/website.

transactional Video On Demand (TVOD)

TVOD is an OTT service that provides streaming video on a pay-as-you-view basis. It is a digital manifestation of pay-per-view (PPV), that enable one-off purchases and often time-limited access. Apple's iTunes on Apple TV is a prime example.


See user-generated content.


Individual users, as represented by a unique user ID. A unique user ID is not associated in any way with personally identifiable information (PII), so it cannot identify a specific unique individual. Also, an individual may be associated with multiple user IDs due to clearing browser cookies or using multiple browsers and multiple devices. Additionally, for mobile devices, a unique user ID may be associated with multiple device IDs (for example,  Apple IDFA, OpenUDID, and others). See reach to learn more about individual users/user IDs.

unique app identifier

The mechanism through which devices allow apps to pass user identifiers to audiences. Historically unavailable to CTV apps and, therefore, buyers.

unique user

Individual users, as represented by a unique user ID. A unique user ID is not associated in any way with personally identifiable information (PII), so it cannot identify a specific unique individual. Also, an individual may be associated with multiple user IDs due to clearing browser cookies or using multiple browsers and multiple devices. Additionally, for mobile devices, a unique user ID may be associated with multiple device IDs (for example, Apple IDFA, OpenUDID, and others). See reach to learn more about individual users/user IDs.

unique user ID

Also sometimes called a UUID. A unique, anonymous user ID for a given user profile that may be stored in a user's browser cookie and/or in the a server-side cookie store. Ad traffickers are not permitted to associate these IDs in any way with personally identifiable information (PII),and user IDs do not necessarily equate to a unique individual. An individual may also be associated with multiple user IDs due to clearing cookies or using multiple browsers and multiple devices. Additionally, for mobile devices, a unique user ID may be associated with multiple device IDs (for example, Apple IDFA, OpenUDID, etc.).

universe estimate (UE)

Total persons or homes in a given population.


A target customer for advertisers. The person browsing the web who will see an ad.

user agent

This usually refers to a browser application. For example, Mozilla 5.0 is a specific user agent.

user data

Information about users that makes them more valuable to advertisers. User data can include age, gender, location, intent to purchase, demographics, psychographics, wealth, past purchases, and more. User data is generally associated with a UUID found in a cookie rather than any personally identifiable information. User data is distinct from contextual data. Often used interchangeably with segment data and audience data.

user data store

A place where data about a user is stored. In online advertising, this often refers to a user's browser cookie. Sometimes, certain user data may be stored server-side for a limited period of time. This data is periodically expunged from server records in order to prevent it from drastically slowing server function, and does not contain personally identifiable information (PII).

user-generated content (UGC)

Content on a website that was posted by users and not a centralized publisher. This includes social media posts as well as blogs, wikis, podcasting, images, videos, audio files, and other forms of media created and posted by users of an online system or service. Some sites support user content through advertising. Others are supported by donations, subscription fees, or a combination of methods. Examples of sites that emphasize or are built around user-generated content include Facebook, Twitter, Instagram, Pinterest, Wikipedia, YouTube, Vine, and SoundCloud.

user ID

See unique user ID.

user ID mapping

Each buyer and seller may assign their own different IDs to a user. Without knowing that Seller S's user ABC is the same as Buyer B's user 1234, it is impossible for B to value an impression from S. To allow for attribution and valuation, different parties must synchronize their IDs by mapping one ID to another. For example, Xandr assigns every user it sees a unique ID that's stored in the user's browser cookie. The Xandr member or bidder maps the Xandr ID to their internal user ID with the Xandr User ID Mapping Service. Also known as user ID synching.

user sync pixel

A pixel used to synchronize user IDs assigned by different parties during an auction, generally to apply frequency, recency, and other decisioning data. See also user ID mapping.


See unique user ID.


Video Ad Serving Template. A framework for serving ads to a video player. The specification also describes expected player behavior for executing ads that are supplied using VAST. The interaction between the ad and the player is unidirectional, meaning that once the player receives the VAST tag no other interactions are possible except for the activation of select tracking beacons at appropriate times during ad playback. For details, see the Interactive Advertising Bureau (IAB) VAST documentation.


Refers to a company with a specific product or service such as creating or delivering rich media, maintaining a CDN, or providing third-party data.

video ad completion

When a video ad starts and plays through its entire duration to completion.

video ad completion rate

The percentage of all video ads that play through their entire duration to completion. Also known as View Through Rate (VTR) and Video Completion Rate (VCR). Not to be confused with the videocassette recorder.

video level meta-data

Information about a video that is comprised by analyzing its text, images, and content. This meta-data is utilized to categorize and describe video content to ultimately help users search for videos and help marketers with contextual targeting efforts.

video on demand (VOD)

Video content that is viewed after its official release date or original air date and time. VOD content can be found on set top boxes, desktop, mobile and connected TV. It is consumers’ ability to select and view shows at a time of their choosing that has revolutionised consumption. In the UK, for example, just 46% of viewing was attributed to live TV in April 2020.

video quartiles

A quartile is 1/4 of something. Media players fire a series of engagement pixels as the video continues to play. These pixels typically indicate how many quartiles of a video has been played, firing at 25%, 50%, 75%, and 100% completion.


Cost per mille, or thousand, viewable impressions (mille = thousand in Latin). A pricing model in which advertisers pay for every 1000 viewable impressions of their advertisement served. Viewability refers to whether an impression was actually seen by the user, and can be determined according to a variety of methods.


Video Multiple Ad Playlist (VMAP) specification. a framework for serving ads to a video player. The specification also describes expected player behavior for executing ads that are supplied using vast. The interaction between the ad and the player is unidirectional, meaning that once the player receives the vast tag no other interactions are possible except for the activation of select tracking beacons at appropriate times during ad playback. Provides a standardized method for communicating the status of a video ad back to the ad servers in the case where the ad is served from a dynamically selected ad server. It is specifically designed for on-demand video player where the ad response is parsed prior to play. Vast is applicable to linear video ads (such as pre-rolls), non-linear video ads (such as overlays) and companion ads as defined in the IAB digital video ad format guidelines.

virtual MVPD (vMVPD)

New form of digital-only cable alternative which provides access to on-demand and live content delivered over the internet without the traditional network infrastructure (i.e. Direct TV Now, Sling TV, Sony PlayStation Vue).


The protocol between the ad and the video player required to enable ad interactivity and other advanced video advertising functionality. VPAID offers bilateral (two-way) communication between the ad and the video player, and meets the needs of emerging in-stream formats such as nonlinear video ads and interactive linear video ads.


In online advertising, a vendor generally refers to a company with a specific product or service such as creating or delivering rich media, maintaining a CDN, or providing third-party data.


A measure of whether an ad has been seen by a given user. Viewability measurement is achieved using javascript embedded within each creative, which is then called for each individual ad impression. The script launches automatically as the page loads and immediately starts measuring if and when the creative is viewable based on a variety of measures. These may include whether a web or browser tab is in focus, whether a particular ad is in view of a user based on where on the page the user has scrolled to, how long an ad was visible based on these metrics, and other factors. The most commonly used bidding strategy based on viewability is CPVM. In 2015, the Interactive Advertising Bureau (IAB) released industry standards for viewability. To learn more, see the IAB website.

viewability rate

The percentage of video ad impressions that were deemed viewable as per the video viewability definition of the measurement vendor.

viewable video impression

A desktop video ad or mobile video ad that meets the criteria of:

  • Desktop: 50% of the ad’s pixels on an in-focus browser tab in the viewable space of the browser page that has met the time criterion that two continuous seconds of the video advertisement is played.
  • Mobile: 50% of the ad’s pixels on an in-focus browser or a fully downloaded, opened, initialized application, on the viewable space of the device that has met the time criterion that two continuous seconds of the video advertisement is played.
  • For both desktop video and mobile video, the required time is not necessarily the first two seconds of the video ad; any unduplicated content of the ad comprising two continuous seconds qualifies in this regard.

walled gardens

Walled gardens do not allow open access to data or allow access to be served through a third-party ad tech infrastructure. They rigorously gather and protect valuable customer data to build strong, personal connections with users across their networks, and can stop other brands from accessing that information.

weighted average

Calculated by multiplying each program's rating by its duration, summing these products and dividing the total by the sum of the duration.

web mediation

Mediation that takes place over the Web. Web mediation involves trafficking an ad network’s tags. The tags are called when the seller ranks the networks proxy bid higher than any other demand. If the buyer doesn’t take the impression, a passback tag set up by the seller informs the ad network to go to the next highest bidder or ad network.

yield management

Broadly, this term refers to selling the right things to the right customer at the right time for the right price to maximize revenue. In online advertising, it generally refers to maximizing the revenue of publishers and their impressions using tools such as price floors.