How many data types are in c?

There are only 5 built-in types in C. They are char, int, float, double and void. All other types are modified types, user-defined types, or aliases (typedefs). If a modified type does not specify a type, int is assumed, thus a long is a long int while a short is a short int. Both char and int can be modified with the signed or unsigned modifiers. The float and double types are always signed but a double can be modified with long to create a long double. User-defined types include structs and unions. All types can be further modified with the suffix operator to create arrays of the given type. Furthermore, all types can be prefixed with the pointer operator to produce a pointer of the given type.