Appearing in Version 6 Unix,[1] spell was originally written by Stephen C. Johnson of Bell Labs in 1975.

ispell had a user interface for showing the spelling mistakes in context and suggesting how to correct them.

Modern spell-checkers for Unix and Linux systems, such as aspell, MySpell and hunspell, support a multitude of different languages and character sets.

The Single Unix Specification has officially declared Spell a "legacy application", stating that this was done "because there is no known technology that can be used to make it recognise general language for user-specified input without providing a complete dictionary along with the input file.

Instead, in 1996 Thomas Morgan of GNU wrote a simple wrapper to ispell (which was already popular at the time) to replicate spell's original behaviour.