Another feature allowed users to “poke” their friends using the site. The meaning of this ambiguous term was never officially clarified, but that did not stop Harvard students from using it.

“Let’s say some girl would add me on Facebook who I hadn’t really met,” Brown said in an interview last week. “I’d be talking to my roommates and ask, ‘What do you think about this? What does this mean? Is she interested? I’m not sure what to think?’ So they’d say, ‘Well, send her a poke and see what happens.’”

“I like the poke,” Brown added.

The features added a new dimension to social interactions on campus, early users say.

“We weren’t quite sure how the online social dynamic was going to play out in real life,” said Barbara Eghan ‘05. Because the concept of online “friendship” was so new, Eghan explained, “it felt like a really big deal to say you were friends with somebody, or to unfriend somebody.”

“We weren’t quite sure what the rules of it were,” she added. “If you reject somebody as a friend or ignore their request, are they going to get a note that says you’ve rejected them?”

That dynamic was quickly complicated further as the network began to expand beyond Cambridge. By March, the site had gained strong footholds at Columbia, Stanford, and Yale and attracted its 10,000th subscriber.

But amid the social network’s rapid success, some users at Harvard worried that thefacebook’s expansion might alter their experience with the site.

“There was this chatter among the early users that it was losing its exclusivity, losing what made it special,” Eghan said.

DROPPING OUT

As the site grew and questions proliferated, so too did the profile of its creator.

By the time Zuckerberg sat for his final exams in May 2004, thefacebook had undergone nationwide expansion and was approaching its 100,000th user. When Zuckerberg finished those finals, he and his team—Dustin A. Moskovitz '06-'07, Andrew K. McCollum ’06-’07, and a group of interns—headed for Palo Alto, Calif. In June, the company changed its name to Facebook. Co-founder Eduardo Saverin '06 did not make the trip to Palo Alto. Christopher R. Hughes '06, who did, ultimately stayed on as the company's spokesperson, but Saverin was soon pushed out of the company.

Zuckerberg never came back to Harvard as a student. He did return after dropping out in 2005 to build the staff of his growing company.

Eghan recalled early recruitment events, often staged outside the Science Center, noting that  they were “heavily attended” by undergraduates. On another occasion, Zuckerberg, in sandals and a t-shirt, appeared before a meeting of CS50.