ASCII stands for American Standard Code for Information Interchange, a code created for the use of teletype operators. It is pronounced /ASK ee/, not A-S-C-I-I. The ASCII code is limited to a specific set of 128 characters, of which the first 32 are set aside, and the remaining 98 include all 26 letters of the alphabet in capital and lowercase, the digits from zero through nine, punctuation marks — exclamation mark, left and right parenthesis and curly and square brackets, comma, hyphen, period, colon, semicolon, single and double quote marks, and question mark — the grave and circumflex accent, front slash, backslash, and upright slash, hashmark, dollar sign, percent sign, ampersand, asterisk, underscore, plus sign, and tilde. These are the characters used in ASCII art, and the whole collection looks like this:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
a b c d e f g h I j k l m n o p q r s t u v w x y z
1 2 3 4 5 6 7 8 9 0
! ( ) { } [ ], – . : ; ‘ “ ?
` ˆ / | # $ % & * _ + ~
These are named in logical groups, but if the last three groups are rearranged, it becomes clear that they are mostly the upper and lowercase versions on certain keyboard keys, just as the alphabet is
~ ! @ # $ % ^ & * ( ) _ + { } | : “ ?
` 1 2 3 4 5 6 7 8 9 0 – = [ ] ; ‘ /
The remaining characters are the period and comma, for which the uppercase elements on their keys are not used.
To create ASCII art, the specified characters are arranged on lines, with spaces in between, to create the lines, shapes, and shading of images, sometimes forming representational shapes, and sometimes aiming only to create an overall impression. While there are some programs to convert images to ASCII art — sometimes called ASCII art generators — their success varies: some have much better results than others. ASCII art is often built in a text editor so as not to introduce any unwanted formatting because the spacing is crucial to the success of the piece. There are also ASCII editors for authoring ASCII art. Emoticons may be considered the simplest form of ASCII art.