An identifier is a creation of a programmer which may refer to names of variables, arrays, classes, functions etc. the following are the rules that govern the naming of identifiers in C++ language:
i. Uppercase and lowercase letters are distinct
ii. It is only the alphabetic characters, digits and underscores that are allowed
iii. The name of the identifier cannot start with a digit
iv. A declared keyword cannot be used as a variable name
v. There is no limit on the length of the identifier’s name
Kavungya answered the question on May 15, 2019 at 14:41