Spell Checker

What Does Spell Checker Mean?

A spell checker is an application, program or a function of a program which determines the correctness of the spelling of a given word based on the language set being used. It can either be a standalone program or part of a larger program which operates on blocks of text such as a word processor, search engine or an email client.


A spell checker is also known as spell check.

Techopedia Explains Spell Checker

Spell checkers are usually a standard inclusion of any word processor or any application which requires users to input large blocks of text, such as the content management portions of Web applications. Though common to the point that people take them for granted today, spell checkers were considered exciting research under the branch of artificial intelligence back in 1957. The first official spell checker application, not simply as research material, was created by Ralph Gorin and called Spell for the DEC PDP-10. It was made in the Artificial Intelligence Laboratory at Stanford University in February 1971 and became widely available for mainframe computers that decade. The first spell checkers for personal computers appeared for the TRS-80 and CP/M computers in 1980 followed by packages for IBM computers in 1981.

The spell checking process is:

  • Scan blocks of text and extract individual words.
  • Compare each extracted word to known words contained in a dictionary file of correctly spelled words, which may also contain punctuation and grammatical rules.
  • Morphologic algorithms might also be applied for handling alternative forms of words used in different grammatical scenarios.
  • Mark the words with incorrect spelling and offer the correct spelling to the user. Some spell checkers change the incorrect words automatically if the setting is activated.

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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.