We’ll soon discuss the type
double for specifying real numbers, and the type
char for specifying character data. Real numbers are numbers with decimal points, such as 3.4, 0.0 and –11.19. A
char variable may hold only a single lowercase letter, a single uppercase letter, a single digit or a single special character (e.g.,
*). Types such as
char are called fundamental types. Fundamental-type names consist of one or more keywords and therefore must appear in all lowercase letters. Appendix C contains the complete list of fundamental types.