Java Collections- Everything you want to know

Collection is an interface - is a framework which allows for using and manipulating collections.




Set- A collection that cannot contain duplicate elements.
2. Elements are in unordered manner.

List- A collection that can contain duplicate elements.
Elements are in ordered manner.

Read more about List here


Map and HashMap
Map is a n interface and Hash Map is class that implements it.

Iterator:1. Used to iterate over collections.
2. Move only in forward direction.

List Iterator : Used to iterate over List Collection specifically.
2. can traverse in both forward and backward direction.