American Standard for Information Interchange

What Does American Standard for Information Interchange Mean?

American Standard for Information Interchange (ASCII) is a method of encoding characters that is based on the order of alphabetic characters in the English language.


ASCII integer representations have printable and nonprintable subsets. Printable characters are normal characters, and nonprintable characters are characters used to represent keyboard keys, e.g., backspace, delete, and return.

Techopedia Explains American Standard for Information Interchange

Technically, ASCII is 7-bit representing only 128 characters (0-127). The range 0-31 are control characters, with 32-127 representing alphabetical characters from A to Z, numerals from 0 to 9 and punctuation marks (though not in that order). ASCII only may be used to encode U.S. English.

Some people confuse codes above 128-255 to be ASCII, but technically speaking, they are not. As computers evolved, it became common to use an 8-bit byte. This last character allowed for an extra 128 characters, which is known as extended ASCII. Different systems implement extended ASCII differently, so there are compatibility issues that aren’t encountered in the first 128 characters.


Related Terms

Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.