The Android Support Library is not actually a single library, but rather a collection of libraries that can roughly be divided into two groups: compatibility and component libraries. For details, please see Understanding the Android Support Library.

library that contains the annotations for Android Jetpack.

a static library that you can add to your Android application in order to use APIs that are either not available for older platform versions or utility APIs that aren't a part of the framework APIs.

perform actions in response to a change in the lifecycle status of another component, such as activities and fragments.

Provides a stable but relatively compact binary serialization format that can be passed across processes or persisted safely.

Provides a stable but relatively compact binary serialization format that can be passed across processes or persisted safely.

Provides a stable but relatively compact binary serialization format that can be passed across processes or persisted safely.