Purpose of the char type
The char type has two purposes.
1 - To represent whole numbers in the range from -128 to +127 or 0 to 255 as indicated earlier.
2 - To represent characters as eight-bit numeric values in order to make it possible to represent the following internally in the computer:
This is accomplished by assigning a numeric value to each character, much as you may have done to create secret codes when you were a child.
The actual character codes used in many computers are shown at http://www.lookuptables.com/.