Computing has come a long way. Take a look at this clip of the Harwell Dekatron, otherwise known as the Wolverhampton Instrument for Teaching Computation (WITCH). The supercomputer from 1951 was restored over a period of three years by experts at England's National Museum of Computing in Bletchley Park. This week, they rebooted the beast in front of reporters.

And what a beast it is. The world's oldest original working digital computer is the size of a garage door and resembles something from a campy science-fiction flick about Martian invaders. True its functionality is rather modest by today's standards (it can multiply two numbers in less than 10 seconds, for example), but darned if it isn't impressive to watch. Lights blink, tubes whir and switches flicker.

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The BBC's Mark Gregory reports (at 13:55 in the broadcast) that the computer weighs about two and a half tons and comes from a time when there were really just a handful of supercomputers in the world. Restoration expert Kevin Morrell explains that "the alternative at this stage using mechanical calculators and slide rules."

Morrell continued: "This machine was built at Harwell, which is the U.K.'s atomic energy research establishment." The computer was built to take the tedious but necessary work of performing calculations away from the mathematicians and let them think about the big picture. The WITCH wasn't fast, but it was accurate. And when you're dealing with anything atomic, accuracy is kind of important.