The Token is an identifier. It can be constant, keyword, string literal, etc. A token is the smallest individual unit in a program. C has the following tokens:
Identifiers: Identifiers refer to the name of the variables.
Keywords: Keywords are the predefined words that are explained by the compiler.
Constants: Constants are the fixed values that cannot be changed during the execution of a program.
Operators: An operator is a symbol that performs the particular operation.
Special characters: All the characters except alphabets and digits are treated as special characters.