“I do not know if you ever have created a search engine with PHP, but if you have done, you wanted to make sure that as Google and correct a user when it is wrong to do a search. But only create such a system can become throughout a project, and usually not worth spending all that time . But everything changes when is another who believes that system just for you and lets you use …”
interesting class that uses PHP the API Spelling Suggestion of Yahoo in order to return a “Did you mean …” to make a query. Demo