Difference between Identity column and Primary Key?

Answer:

Identity Column:
1.Identity column is auto incremented
2.Incremented numeric values only
3.Only one Identity column in table
4.All identity column is an primary Key
5.Values cannot be updated

Primary Key:
1.Primary Key value will be entered by the user.
2.Can be created more than one column (composite primary key).
3.All primary key is not an identity column.
4.Can be update the value
5.Can be refer by other table as a foreign key.