The C programming language provides the programmer with a set of data types for storing information and building up data types that are not part of the language itself. The former data types are called built-in types, and the latter are called user-defined types.
The three basic built-in types are these:
Characters (char), such as a
Integer numbers (int), such as 42
Floating-point numbers (float), such as 42.42 or 1234.5678
The integer data types come in two flavors—signed and unsigned—which permit the programmer to specify values greater than and less than zero. In other words, positive and negative numbers.
All of these basic built-in types have a specific size (amount of memory required) and range of values that they can represent. ...