Bundles are generally used for passing data between various Android activities. It depends on you what type of values you want to pass, but bundles can hold all types of values and pass them to the new activity.
You can use it like this:
Intent intent = new...
Intent(getApplicationContext(), SecondActivity.class);
intent.putExtra("myKey", AnyValue);
startActivity(intent);
You can get the passed values by doing:
Bundle extras = intent.getExtras();
String tmp = extras.getString("myKey");
You can find more info at:
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