Collections are one of the most common methods for storing data locally within your PowerApp, and once you start developing, you will find that they are extremely useful in a number of different ways. They can be built dynamically while you're running your app, as well as when your app loads. This means you could use it to retrieve data from a data source and store it locally so that it can be manipulated before being written back. In this chapter, we are going to use collections to build data that we can then interact with using our output controls, galleries, and tables.
A collection can be compared to a table, where you have a number of rows of data with each attribute being expressed as a column. Collections can store arrays of data within them, so they're slightly more complex than just a simple data table, but the premise is the same.
Filling collections
When you're filling in a collection, you can do two different things...