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Steve Ballmer, who has just passed Bill Gates to become Microsoft’s largest shareholder, has kept a relatively low profile since leaving the software maker.

However, he did give a speech in March at Oxford Union — with highlights recently posted to YouTube.

“I’m nervous,” Ballmer said at the outset of the talk, which he noted was his first one since leaving Microsoft in February. “It may be my last, too, if it doesn’t go well.”

In the presentation, he talked about Microsoft and Apple as being two-trick ponies.

“They’re an amazing company because they did two tricks,” Ballmer said of Apple, according to GeekWire. “We’re an amazing company because we did two tricks.”

Apple’s tricks, according to Ballmer, were the Mac and low-power touch computing, starting with the iPod. Microsoft’s, by his calculation, were the personal computer and then getting that technology adopted by businesses.

Microsoft’s third trick, though, has proven to be, well, tricky.

“We’ve done two tricks and those will go for a lot of years,” he said. “But in our industry, you have to do a third trick.”

Ballmer is also slated next month to give the graduation speech at the University of Washington.

Here’s what he had to say about Facebook:

and here’s Ballmer on open source software: