What is an Identifier?

Identifier is the name given to the variable, function, array, structure etc.

There are certain rules which an identifier must follow:
1. It should not be a keyword which is available in the language.
2. First character of identifier should be an alphabet or underscore.
3. No other special character is allowed except underscore (_).
4. Both the cases that are upper case and lower case are allowed. An identifier student is not same as STUDENT.