When building or integrating with APIs, you'll often want to create and store a collection of endpoints and requests in order to test quickly and effectively. There are a number of tools to help with this, but the one I use most often is Postman.
To make things easier, postman has a concept of collections, which is a collection of endpoints, and environments, which allow you to store variables and information for a particular environment such as test or production.
Many APIs have some kind of short-lived authorization token that must be added to the header, and if you have endpoints in Postman that are saved with variables, it can be a hassle to manually update the auth token (or anything else) every time it changes
