Summary
In this module, you started by learning what a pipeline is.
A pipeline is a set of commands connected by the pipe (|) character. The idea is to have the output of one command serve as the input to the next command.
As part of constructing the pipeline, you learned that you first need to evaluate whether a command fits, and can be added as the next command in the pipeline. A command fits if its output matches the input that's needed for the next command to run.
The Get-Help command helps you inspect the command, and the INPUT and PARAMETERS sections can help you understand what types of input a command accepts. For pipeline input, you need to find parameters that have the property Accept pipeline input? set to True.
There's also an evaluation order that reveals how the input is analyzed for validity. Input can be considered valid in either of two main ways. The first way is called By value, which means that the input matches an array to a specific type. The second way, By property name, means that whatever type of object is passed in, it must have a property with a particular name.
Finally, you learned about filtering and formatting. The filtering left concept is important because it dictates that you should filter as close to the data source as possible. That is, it should be input as far left, or early, in the statement as possible. This placement is especially important when you work on large data stores and you need data to be returned over the network. Formatting right means that any output formatting should be placed as far to the right, or late, in the statement as possible.