One of the great aristocrats of the internet, Jimmy "Jimbo" Wales, can be forgiven for having a spring in his step as he walks the London streets.

A decade after he founded Wikipedia, the trove of online information has grown to 17 million articles and attracts a monthly audience of 400 million users, making it the fifth most popular website in the world.

Wales is unconcerned by the cold in Britain, having just returned from Russia where he met President Dmitry Medvedev, one of the many international excursions he makes to promote and explain a project that depends on the dedication of an army of unpaid contributors. Besides, Wales needs to acclimatise to British winters, intending as he does to make London his future home.

This Anglophile streak extends to a fixation with the House of Lords which, somewhat bizarrely, is identified by the Alabama-born digital media entrepreneur as the subject area he spends most time studying on Wikipedia, sometimes editing the articles himself. He has become acquainted with numerous peers, including Lord Peter Mandelson.

If Wikipedia - which some estimates have valued at US$5 billion ($6.5 billion) - were not a non-profit venture, shunning advertisers and overseen by a charitable foundation (of which he is emeritus chairman), Wales would possess unimaginable wealth. As it is, he is making his annual appeal to Wikipedia users for funding, this year seeking US$16 million, in order to maintain independence by avoiding dependence on major benefactors.

He made his own small fortune as a futures and options trader in Chicago before even dabbling in the internet. And, having established Wikipedia with his then partner, Larry Sanger, on January 15, 2001, Wales has since set up a separate for-profit business, Wikia, which carries advertising and caters to more than 100,000 "wiki" groups with specialist interests ranging from The Muppet Show to the cult computer game World of Warcraft.

Wales, 44, admits the scale of Wikipedia's growth has outstripped even his famed self-confidence.

"[With] 400 million people a month visiting the site it has become really a fundamental part of the information infrastructure of the world," he says.

"I didn't imagine this. It just didn't occur to me, sitting at my computer, that I would end up travelling all over the world."

Before starting Wikipedia, Wales' only foreign trips had been to Canada and Mexico. Now he travels to speak at global economic events, and his social network includes Bono, Richard Branson, Al Gore and Jimmy Carter.

But as he spreads his gospel he must overcome an unforeseen and potentially damaging misapprehension: the commonly held view Wikipedia is attached to WikiLeaks, the scourge of the Western establishment for its publication of confidential documents.

"The most important message ... is that we have absolutely nothing to do with WikiLeaks," says Wales, who is irritated by the name of Assange's site. "What they're doing is not really a wiki. The essence of wiki is a collaborative editing process and they're just getting documents from people and releasing them. There's no collaborative editing going on."

That's not to say that, as a champion of free speech, Wales doesn't have some sympathy with WikiLeaks.

"It's complicated. In open and free societies it's really important that people who have evidence of wrongdoing have some avenue to make that known. At the same time I would echo some of the concerns raised by Amnesty International and Reporters Without Borders, and counsel that WikiLeaks should be careful about the ramifications of what they're releasing, and work with people to make sure that what they're doing is providing a useful public service."

Wikipedia, he has no doubt, is doing just that. The site was once lampooned widely for the untruths that resulted from allowing anyone to edit its entries. Wikipedia's own Wikipedia page contains the acknowledgement that "some media sources satirise Wikipedia's susceptibility to inserted inaccuracies".

Wales believes the quality of articles has improved markedly. This is partly because of protection measures introduced recently for the most sensitive articles (such as the biography of George W. Bush), where all changes are subject to a delay so that they can be reviewed by an established Wikipedia editor.

"Where we've gotten to now is fairness - we don't get these stories that we are a crazy bunch of people and it is complete garbage," says Wales, acknowledging an institution with the influence of Wikipedia is rightfully held to account.

Where Wikipedia can improve, he admits, is in the diversity of its contributors. About 100,000 volunteers are involved in editing on at least a monthly basis, allowing the site to operate with a tiny staff of about 45. But editors are "over 80 per cent male and tech-savvy", he says, so subjects such as "sociology or Elizabethan poetry" can be neglected.

So Wikipedia will begin its second decade by making it easier for less tech-minded users to edit pages. In future, users are likely to be encouraged to give ratings to the pages they read, encouraging them to be more interactive with the site.

Not that Wales wants everyone to be an editor. "We've never been about participation for participation's sake. We are trying to build an encyclopaedia."

Similarly, he is unconcerned that growth in new articles on English Wikipedia seems to be slowing. "All the easy topics have been written about.. It's not about rapidly creating the maximum number of pages ... The point is to create useful pages."

Wales' focus is moving east, to India in particular, where in the next six months Wikipedia will open its first office outside of the United States, probably in Mumbai or Bangalore. Increasing the number of articles in Indian languages is "really key", he says. "We have 50,000 articles in Hindi and tens of thousands in other languages."

There is still so much to do. Africa remains largely undocumented, especially in native languages. "One of the big keys is increasing the diversity of the contributor base," says Wales. He cites a need for more contributions in Arabic but is pleased that the linguistic breadth of Wikipedia - which has 262 language editions - gives it a remarkable reach in the developing world.

Where many of the great digital media brands have lost their way - AOL, MySpace, Yahoo! - Wikipedia has maintained its relevance. According to Sergey Brin, a founder of Google, Wikipedia is "one of the greatest triumphs of the internet".

Wales does not have the same profile as some of the other great online pioneers. But as a character he is more red-blooded than other famous nerds such as Bill Gates and Mark Zuckerberg. After working as a futures trader he set up Bomis, a male-oriented dot-com business focusing on "babes" and sport. He has been married twice and has a daughter with his second wife. Back then in Alabama, where he spent hours poring over the Encyclopaedia Britannica - he had the ambition of being rich and living in Britain.

He achieved a geek's dream recently by visiting old Albion's ancient seat of governance and dining with Merlin - Merlin Hay, the 24th Earl of Arroll, who invited him to lunch at his beloved House of Lords.

It seems strange the man behind a concept that gives everyone the chance to contribute to a knowledge resource should be in awe of a chamber that is derided for being undemocratic and anachronistic.

But Wales responds by comparing the internal structure of Wikipedia with the United Kingdom's system of government.

He talks of the lack of a written constitution, refers to the website's highest body (its arbitration committee), and notes "if you become an administrator in Wikipedia, you are pretty much in for life as long as you behave yourself".

BORN: August 7, 1966, Huntsville, Alabama

EDUCATED: Randolph School, Huntsville; Auburn University, Alabama, University of Alabama; Indiana University

CAREER: While a student, Wales worked at a grocery store where he met his first wife. Made his fortune as a futures trader in Chicago before deciding to become an internet entrepreneur and setting up Bomis, a search engine aimed at young men.

The prototype, Nupedia, morphed into Wikipedia after Wales hired Larry Sanger, who introduced the "wiki" concept that allowed outside contributors to create and edit the pages. Today the site has 400 million monthly users and runs to 17 million articles

FAMILY: Twice married, with one daughter from his second marriage, Wales lives in Florida. Has a girlfriend with a home in London.