Radio 4's PM programme reports on the anti-cheating software

But the days of such dubious enterprises could be numbered, as a computer program has been developed by software consultant, David Woolls, that can identify whether students have really written essays themselves.

The software, first used in forensic testing of written testimonies in court, is now ready to be applied to students' work. The software examines sentence structure, vocabulary, phrases and syntax, with each analysis showing the particular style of each writer.

The University of Birmingham's Professor Coulthard hopes the software will deter would-be cheats

If there are extreme similarities in these profiles, it is likely that they are by the same author, an analysis that could be used to test claims of plagiarism.

Also if students' essays varied greatly from their usual style, there might questions to answer about where the essays originated.

Professor Malcolm Coulthard of the University of Birmingham says that such electronic assistance will help both in catching cheats and in deterring others from attempting to cheat.

Dr Coulthard says that an increased workload in universities means that it is less likely that lecturers will be familiar with their students' writing styles and that the software check would make it much easier to identify copied work.

The software will be particularly useful in guarding against the apparent upsurge in the use by students of Websites offering essays for sale.

"There are Websites where you can buy essays for as little as £10. And you can get a made-to-measure essay for £100," says student union representative, Oliver Chapman.

Students using these Internet sites will now face an electronic watchdog, which will be able to detect where a students' essay is all or partly the work of someone else.