Sets, Stacks & Queues

Other collections, similar to lists, are available in Java with in particular:

1. Set
   When ordering is not important and duplicate elements are omitted.
   As a limit, Set does not proposes standard mathematical operations on sets: union, intersection, difference, etc.

2. Stack
   That are "First In - Last Out" structures with push and pop operations.

3. Queue
   That are "First In - First Out" structures with add (to tail) and poll (to get head) operations.