American Standard Code for Information Interchange
ASCII Character Set
A char variable in C++ is a one-byte memory location where a single character
value can be stored. Because one byte can hold values between 0 and 255 that means
there are up to 256 different characters in the ASCII character set. These are
usually broken down into two groups. The first, with values from 0 to 127 are
considered the "Standard" ASCII character set. Characters with values
from 128 to 255 are the "Extended" character set.

The ASCII Character Set
To actually display most of the extended character set you must use an escape
character in a string to create that character. The escape character is
"\xnnn". Where nnn is the hexidecimal value for the character.

The Extended ASCII Character Set