What is identifier in C++ programming language?
In C++, and other programming languages, an identifier is a name that is assigned by the user for a program element such as variable, type, template, class, function or namespace.
RULES FOR NAMING IDENTIFIER:
-Identifiers are case sensitive because C++ is case sensitive i.e. uppercase letters and lowercase letters are different.
-You cannot start name of an identifier with a digit whereas underscore can be used as first character while naming identifier.
-Other special characters are not allowed while naming an identifier.
-You cannot use keywords as identifier.