Identifier

Identifiers are names for objects and entities.

Python Example

A list of Python reserved words that cannot be used as identifiers can be found here: https://docs.python.org/2.5/ref/keywords.html 

# Identifiers are names for variables, functions, modules and other objects. 
number1 = 20
string1 = "This is a string."
def my_print(parameter1, parameter2):
    print(str(parameter1), str(parameter2))

# Use identifiers.
my_print(number1, string1)