In Android, a fragment is a modular section of an activity. It has its own lifecycle and receives its own input events, and it can be added or removed from an activity while the activity is running. Fragments are typically used to create user interfaces that can be reused across multiple activities, or to create more dynamic and flexible user interfaces that can respond to different screen sizes and orientations.

Topics Meaning Reference Videos
Fragment Lifecycle Understanding the lifecycle events that happen to a fragment https://developer.android.com/guide/components/fragments#Lifecycle
Creating a Fragment Steps and instructions on creating a new fragment https://developer.android.com/training/basics/fragments/creating
Adding a Fragment to an Activity How to add a fragment to an activity https://developer.android.com/training/basics/fragments/fragment-ui
Communicating between Fragments How to pass data between fragments and activities https://developer.android.com/training/basics/fragments/communicating
Saving Fragment State How to save and restore a fragment's state https://developer.android.com/guide/fragments/saving-state
Fragment Transactions How to add, remove, replace, and perform other fragment transactions https://developer.android.com/guide/fragments/transactions
Fragment Layouts How to create layouts for fragments https://developer.android.com/guide/fragments/create-ui
DialogFragment How to use a fragment as a dialog https://developer.android.com/guide/fragments/dialog
ListFragment How to use a fragment to display a list of items https://developer.android.com/guide/components/fragments-list
FragmentManager How to manage fragments in your activity https://developer.android.com/guide/components/fragments#Managing