What is hash? what is index?

What is hash is it storing data method or retreiving. what is index and what r implementing methods of it?

Hashing is a technique to store and access records in the database. It is performed with the help of hashing algorithm that converts a primary key value into a record address. Most hashing algorithms use the technique of dividing each primary key value by a suitable prime number and then using the remainder of the division as the relative storage location.
For details please visit: http://searchsqlserver.techtarget.com/definition/hashing
2) Indexes are created on tables by using Create Index stement, for rapid access of records. Mostly used implementation methods are B+ trees, inverted files and linked lists.