page_title: Harwell computer
section_title: More information
hierarchical_section_title: Harwell computer / More information
caption_attribution_description: English: Photo of Harwell Dekatron Computer running from the front.
context_page_description: The Harwell computer, later known as the Wolverhampton Instrument for Teaching Computing from Harwell, or the Harwell Dekatron Computer, is an early British relay-based computer of the 1950s. From 2009 to 2012, it was restored at the National Museum of Computing. In 2013, for the second time, the Guinness Book of World Records recognised it as the world's oldest working digital computer, following its restoration. It previously held the title for several years until it was decommissioned in 1973. The museum uses the computer's visual, dekatron-based memory to teach schoolchildren about computers.
context_section_description: A short book has been produced about the machine and the restoration project that also includes a brief technical description of the machine.
  There are also a series of short video recordings of the machine in operation on YouTube. A search for Harwell Dekatron will identify these.
caption: The complete computer viewed from the front
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