The Mac had already been shown off to the press in the fall of 1983, and the 1984 ad broadcast during the Super Bowl in January made a big public splash. But it wasn't until January 30, 1984 that Steve Jobs and other members of the Macintosh team would show the new computer to the public - specifically, a gathering of the Boston Computer Society (BCS). Harry McCracken has all the details over at Time.
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