Wikipedia has exploded over the last few years and research found that 36% of Americans online use the service.

A study from the Pew Centre for the American Life Project has revealed that, despite questions over the accuracy of some of its entries, the online encyclopaedia remains a popular source of information.

Most interesting is that for a site not completely accurate, half of people with a degree or more use the online encyclopaedia to reference material, and 42% of people who earn more than £37,000 consult the website for information and details.

The online encyclopaedia has more than 5.3 million entries in 251 different languages, 1.7 million of which are in English.

However sites are now challenging the phenomenon, with Conservapedia seeking to counter the "liberal bias" of Wikipedia practising with Bible content. And, one of the founders of Wikipedia has launched Citizendium - which aims to improve accuracy of information.