2. The C character set

C uses the uppercase letter A to Z, the lowercase letters a to z, the digits 0 to 9, and certain special characters as building blocks to form basic program elements ( e.g., constants, variables, operators, expressions, etc.).

Some of the special characters are listed below:

+ - * ~ % / & ( ) { } [ ] ? " < > ! ; :

Most versions of the language also allow certain other characters, such as @ and $, to be included within strings and comments.

C uses certain combinations of these characters, such as \b,\n and \t, to represent special conditions such as backspace, new line, and horizontal tab, respectively

These character combinations are known as escape sequences.