Bundle is technique of mapping String values to various Parcelable types which stores primitive datatypes and objects as couple key-value. Bundle is most often used for passing data through various Activities. It Provides putType() and getType() methods for storing and retrieving data from it. Bundle as parameter of onCreate() Activity’s life-cycle method can be used when you want to save data when device orientation is changed (in this case activity is destroyed and created again with non null parameter as Bundle).

Demonstration examples of usage: 

Passing primitive datatypes through Activities:

Intent i = new Intent(ActivityContext, TargetActivity.class);

Bundle dataMap = new Bundle();

dataMap.putString(“key”, “value”);

dataMap.putInt(“key”, 1);

i.putExtras(dataMap); startActivity(i);