The applications that let the users compose text, for instance, of articles or e-mail messages, can benefit of text spelling features as they let the users review and eventually fix spelling mistakes before submitting the final version of the texts that are composed.

PHP comes with text spelling extensions like pspell but in some installations these extensions are not available.

This class provides a text spelling solution completely based on PHP code that only uses basic functions

The class makes it possible to provide text spelling features without depending on the availability of PHP spelling extensions.

You can try it here. The code is also downloadable here. I won the December 2004 phpclasses.org prize for this application.