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The Computer History Museum in Mountain View, California holds the largest collection of computing artifacts in the world, including one of three working DEC PDP-1 machines, an IBM 1401 restored over roughly a decade by retired IBM engineers, a Cray-1, an Apple I, and Google's first production server. A working Babbage Difference Engine No. 2 was demonstrated there from 2008 to 2016.
Full transcript
The Machine Babbage Never Built
Charles Babbage designed a mechanical calculating engine in the eighteen forties. He drew it in obsessive detail and he never finished building one. For a century and a half it was a famous might have been. The Science Museum in London finally built one in 2002, 153 years after it was drawn. From 2008 until the 31st of January, 2016, this museum had it on loan from Nathan Myhrvold, built from Babbage's original drawings with no design changes. It is 8,000 parts, five tons and 11 feet long, and it computes. Visitors who caught it watched a docent turn the crank and saw a Victorian idea execute; the machine has since gone back to its owner. It is the single best argument in this building that computing is older than electricity, and most visitors walk past it looking for the iPhones.
Three Working PDP-1s
Somewhere in this building is one of three working PDP-1 computers left on earth. It is from 1959, it cost about a hundred and twenty thousand dollars, and it has a round screen. On that screen the museum runs Spacewar, written in 1962 by students at MIT — arguably the first real video game, made because someone wanted to show off what the machine could do. Volunteers demonstrate it, and sometimes you get to play. Nearby is an IBM 1401, the machine that put computing into ordinary businesses in the nineteen sixties. It was restored over about ten years by a team of volunteers, many of them retired IBM engineers who had originally serviced these machines. They brought back the hardware they built their careers on, and it prints.
The First Google Server
Also here: Google's first production server. Not a rack — a stack of bare boards on a frame, held together with the cheapest materials that would work, because two graduate students needed disk space more than they needed dignity. That is the real lesson of this museum, and the reason it belongs in this valley rather than in Washington. Almost nothing here looks impressive at the moment it was made. The Cray one supercomputer looks like furniture. The Apple one is a bare board. One practical thing: **check the demonstration schedule the moment you walk in.** The PDP-1 and the IBM 1401 only run at specific times with volunteers present, and those two demonstrations are the reason to come here rather than read about it. Start the rest of your visit around them.