What is Java Hashtable and How it works? What is Java Hashmap and How it works?

What is Java Hashtable and How it works?
What is Java Hashmap and How it works?

What is the difference between Hashtable and Hashmap?
How do you insert a record (Key/Value Pair) in Map?
What happens when you insert a new record in the Hashtable?
What's the role of Equals and HashCode?
What is Collison?
How does system resolves collision?
What is Load Factor?