NEW YORK — Long before social networks such as MySpace and Facebook became the darlings of Web 2.0, engineers were active in Usenet or Newsgroups, asking questions and helping one another via the Internet. They routinely uploaded files on FTP sites to share with engineers.

Just as teenagers crave fame, fortune and friendship on MySpace, engineers also seek recognition and camaraderie among their peers on the Internet. Like anyone, they long for an audience where they can strut their stuff.

The preferred Internet hangouts for engineers, though, are user communities, often hosted by technology companies. What they do there may be better described as "social computing" rather than "social networking."

Differences aside, the common denominator of "social computing" and "social networking" is that it's hard to stop. In that vein, Wikipedia's co-founder Jimmy Wales once wrote: "The main thing about Wikipedia is that it is fun and addictive."

More importantly, it offers a place to be solitary and yet social.

In a recent article in The New York Review of Books, Nicholson Baker described the phenomenon: "All big Internet successes--e-mail, AOL chat, Facebook, Gawker, Second Life, YouTube, Daily Kos, World of Warcraft--have a more or less addictive component; they hook you because they are solitary ways to be social: you keep checking in, peeking in, as you would to some noisy party going on downstairs in a house while you're trying to sleep."

MathWorks, a leading software provider for technical computing and model-based design, is witnessing a huge surge in activity in its online user communities. Ned Gulley, a leader for MathWork's user community, cited "a sea change" in the last two years, with the number of visitors to the Matlab site doubling on an annual basis.

Founded in 1984, Mathworks has been hosting a user community called Matlab Central since the early 1990's. As Gulley acknowledged, the company "didn't start from zero." But a few hundred files originally on its FTP site have grown to 7,500. Users add seven to eight new files every day to Matlab's file exchange. Its news group receives new questions constantly, prompting threads of exchanges.

Matlab, originally created to house a community of nearly 1 million users of the computing language of the same name, attracts nearly 400,000 users a month, according to the company.

While MathWorks maintains its storefront, it is "customers, not the company, hosting the site, who bring materials to the Web site," said Gulley. Yair Altman, vice president of R&D at PicScout, a visual content monitoring provider, is an active Matlab user. Altman, based in Israel, first came to MathWork's user community thinking it was an online help site. He quickly found out that the forum offers much more.

Matlab consists of two components: "Forum and "File exchange." Altman calls Matlab's forum "by far the most important" because he finds answers there to questions related to MathWorks "faster and more useful than Google."

"If you find a bug in Microsoft's closed software package, you send an e-mail to its support team. That's as far as you go." With Matlab, "you get direct dialog and responses from people who have been actually using MathWorks," Altman said.

It's addictive. Even when he's swamped, Altman can't help but look up new posts each day. He also submits programs to Matlab's File exchange. "When I get good reviews, I am quite proud of it," he said. Poor reviews from peers elicit the opposite response. "I say to myself, 'That was a perfect submission! Why don't they get it?'" The exercise only motivates him to submit more revisions.