What is a “bundle” in an Android application?

Copied from https://stackoverflow.com/questions/4999991/what-is-a-bundle-in-an-android-application

A mapping from String keys to various Parcelable values. 序列化的键值对集合。

• to pass data between various Android activities.

  Bundles can hold all types of values(可以存储所有类型数据，其实 intent.putExtra也可以存储所有类型数据)

• to pass data from activity to fragment.

• to save and restore state when the screen rotates:

    onCreate(Bundle savedInstanceState)
    onSaveInstanceState(Bundle outState)