Palo Alto, California (CNN) -- President Obama began his "town hall" event at Facebook's offices on Wednesday with an anecdote. "I hate to tell stories about Mark," Obama said, referring to Facebook CEO Mark Zuckerberg, who was moderating the session. As if the two former Harvard students were old friends, Obama then launched into a brief retelling of a dinner party he atttended in February with the 26-year-old computer whiz and about a dozen other tech-industry elites. There, Zuckerberg sat to the president's immediate right. "I'm the guy who got Mark to wear a jacket and tie," Obama said, referring to Zuckerberg, who abandoned his usual T-shirt and hoodie ensemble that day. "Halfway through dinner, he's starting to sweat a bit. It's really uncomfortable for him. I helped him out of his jacket.
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At a Facebook event, President Obama repeatedly poked fun at Facebook's founder
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The pair had met before at a dinner for the president and Silicon Valley elite
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Mark Zuckerberg praised Obama's efforts in education reform
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