Terminology and language conventions

Terminology

Term	Definition
A2DP	Advanced Audio Distribution Profile. This is high-quality stereo audio used for playing back music.
Accessory	A Bluetooth device like a mouse, keyboard, game controller or a headset . All specialized accessories (like audio accessories) are also accessories.
Audio Accessory (Headset)	An accessory that also includes a microphone and speakers and is intended to work with communications software such as Teams. Audio accessory examples include speakerphones and headphones.
AG	Audio Gateway. A device that acts as an Audio Gateway, both for input and output. It is typically a PC or cell phone.
AVRCP	Audio/Video Remote Control Protocol.
AVDTP	Audio/Video Distribution Transport Protocol.
BAS	Battery Service.
Baseband	Baseband is the physical layer of the Bluetooth stack. It is sometimes called the transport or the physical link. Baseband is the preferred term in this document.
Bonding	In Bluetooth security model, bonding is the act of storing the keys created during pairing for use in subsequent connections to form a trusted relationship between a Bluetooth system like a Windows PC and a Bluetooth accessory like a Headset. See also Pairing.
BR	Basic Rate (see also EDR).
CoD	Class of Device. Class of Device is a parameter received during the device discovery procedure on the BR/EDR baseband, indicating the type of device.
Device	See “Accessory”.
Dual Mode Audio Accessory or Dual Mode Headset	A Dual Mode Audio Accessory is one that supports both Bluetooth BR/EDR (aka Bluetooth classic) and Bluetooth LE.
EDR	Enhanced Data Rate. See also BR.
eSCO	Extended Synchronous Connection-Oriented. See also SCO.
HFP	Hands Free Profile is a standard Bluetooth profile that defines the minimum set of functions that can be used in conjunction with a Hands-Free accessory.
LE	Bluetooth Low Energy is a type of Bluetooth technology designed by Bluetooth SIG aimed at novel applications in healthcare and fitness as well as common input and audio accessories for computers and cellphones. Bluetooth LE is independent of Bluetooth BR/EDR and can co-exist with it.
NR	Noise Reduction.
Pairing	In Bluetooth security model pairing is the process for creating one of more shared secret keys vs. Bonding. See also Bonding. The word pairing is commonly used by end users and accessory documentation to mean both pairing and bonding. In this document we will attempt to clearly distinguish these two.
SCO	Synchronous, Connection-Oriented. Bluetooth Hands-Free audio uses SCO and eSCO.
Transport	See baseband. Transport is not used in this document; baseband is the preferred term.
Windows system	A PC or other device that runs Windows with native Bluetooth.
UX	User experience. On the Windows systems this includes dialogs, notifications and toasts, the quick actions settings, and more.

Language conventions

This subsection describes the correct usage of key terms that indicate degree of requirements for processes and data structures. The information here was derived from the Institute of Electrical and Electronics Engineers (IEEE) Style Guide, see https://mentor.ieee.org/myproject/Public/mytools/draft/styleman.pdf.

The following table is identical to the language conventions used in Bluetooth specifications, since most readers are familiar with those conventions. Further clarification of the terms can be found in the Bluetooth Core Specification, Volume 1, Part E, Section 1.

Word	Definition
shall	is required to – used to define requirements.
must	is used to express either a natural consequence of a previously stated mandatory requirement, or an indisputable statement of fact (one that is always true regardless of the circumstances).
will	it is true that – only used in statements of fact.
should	is recommended that – used to indicate that among several possibilities one is recommended as particularly suitable, but not required.
may	is permitted to – used to allow options.
can	is able to – used to relate statements in a causal manner.
is	is defined as – used to further explain elements that are previously required or allowed.
note	Used to indicate text that is included for informational purposes only and is not required in order to implement these guidelines. Each note is clearly designated as a “Note” and set off in a separate paragraph.