Wikipedia is too complicated for many people to modify despite billing itself as "the free encyclopaedia that anyone can edit", its founder has said.
Jimmy Wales told BBC News the site wants a new generation of contributors, including more women.
The online encyclopaedia, which is 10 years old on 15 January, is the world's fifth most popular site.
It aims to increase its users from 400m to 1bn by 2015. But growth requires a new interface, said Mr Wales.
"We have to support our old power users because they build the site," he said. "But we also need to have a ramp for new users".
He said a lot of people were "afraid" to contribute to the site by the sometimes complicated code - known as Wiki mark-up - needed to format entries.
"If you click edit and you see some Wiki syntax and some bizarre table structure - a lot of people are literally afraid.
"They're good people and they don't want to break something.
As well as initiatives such as "adopt a user", that allows experienced Wikipedians to take a new user under their wing, he said his for-profit company Wikia had been doing a lot of work designing simple "what you see is what you get" editing tools.
"We're releasing all of that open source and Wikipedia will probably adopt some of that". BBC News
