char is a special integer type designed for storing single
characters. The integer value of a char corresponds to an ASCII
character. For example, a value of 65 corresponds to the letter
A, 66 corresponds to B, 67 to C, and so on.
As in the table above, unsigned char permits values from 0 to
255, and signed char permits values from -127 (or -128) to 127.
The char type is signed by default on some computers, but
unsigned on others. (See Character conversion table. See Special characters.)
char is used only within arrays; variables meant to hold one
character should be declared int. (See Strings, for more
information on character arrays. See Cast operator demo, for an
example of how to use an integer variable to hold a character value.)