The foundation that runs Wikipedia has finally agreed to pay contributors to the online encyclopedia a modest fee for their work. But it won’t pay the thousands of people who participate in creating the wiki pages — just artists who create “key illustrations” for the site.

The payments are made possible by a $20,000 donation from Philip Greenspun, who said he was moved to give the money because of his experience seeing technical books he had originally published online appear in print.

“In comparing the Web versions to the print versions, I noticed that the publishers’ main contribution to the quality of the books was in adding professionally drawn illustrations,” he wrote in an e-mail message. “It occurred to me that when the dust settled on the Wikipedia versus Britannica question, the likely conclusion would be ‘Wikipedia is more up to date; Britannica has better illustrations.’”

The woman running the project for Wikipedia, Brianna Laugher, says the plan is to create a list of articles that need illustrations and then solicit the work. The first list is expected to have 50 illustrations and be completed this month. Contributors will be able to sign up for an illustration and have two weeks to submit it; if it is accepted, the illustrator will be paid $40.