Difference between HashMap and HashTable

Both HashTable and HashMap implements Map interface but there are some differences between these two.It is one of the most popular questions asked in interview.So prepare well.

                                                    HashMap Vs HashTable

	HashMap	HashTable
Synchronization or thread-safe	HashMap is not synchronized.hence It is better for non-threaded applications.	HashTable is synchronized.This makes it better for multi-threading applications.
Iteration methods	HashMap uses Iterator interface for iteration.	HashTable use enumeration interafce for iterating the values.
Null Values/Keys	HashMap allows one null key and any number of null values.	whereas HashTable does not alloe null key and null values.
Performance	HashMap is faster and uses less memory as it is not synchronized.	HashTable takes more memory and slower than HashMap in performance.
Fail Fast Iterator	The iterator in HashMap is fail fast.	The enumeration in HashTable is not fail fast.

Make sure you study this well.Happy Reading... :)