A literal is a notation for representing a fixed value in source code.
Almost all programming languages have notations for atomic values such as integers, floating-point numbers, and strings, and usually for booleans and characters.
Some also have notations for elements of enumerated types and compound values such as arrays, records, and objects.
An anonymous function is a literal for the function type.
Avoid using literals as "magic constants". You can use literals directly in expressions and statements although it's not always good programming practice.