Extended ASCII Codes
As people gradually required computers to understand additional characters and non-printing characters the ASCII set became restrictive. As with most technology, it took a while to get a single standard for these extra characters and hence there are few varying “extended” sets. The most popular is presented below.
Because of the great diversity of languages around the world, the 16-bit Unicode character set was created to support different character symbols.
Terminology for Numeric Data Representation
The interpretation of numbers on a computer depends greatly on the context in which the number appears.
For the example of decimal 65,
A debugging program would probably display the byte as “41,” which is the hexadecimal notation for this bit pattern.
But if the byte were moved to the video display area of memory by a running program, the letter A would appear onscreen. This is because 01000001 is the ASCII code for the letter A.