Apps Simple concept question regarding fragments/main

[AlexGraal]

Hey guys!

Very brief here.

What are fragments/activites. Why are there two. The tutorial I am following only has the main activity, no fragment. So why and how are the fragments used?

Thanks

 

[alostpacket]

The easiest way to think of fragments is like "mini" activities. (While not 100% technically correct, it is a good starting off point)

An Activity can hold several fragments. They were added in Android 3.0 so you could have split interfaces for tablets. Nowadays, most people use a single Activity and just change fragments to change "screens".

Have a look here at a stack overflow answer I wrote a while back:
android - How many Activities vs Fragments? - Stack Overflow

And here:
Preparing for Handsets | Android Developers Blog