27 lines
1,019 B
Markdown
27 lines
1,019 B
Markdown
---
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tags: [computer-history, memory]
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created: Tuesday, September 24, 2024
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---
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# Magnetic drum memory
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Along with the [Williams_Tube](Williams_Tube_memory.md), another early approach
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to RAM used in 1950s-1960s era of computing.
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A magnetic drum was a metal cylinder coated with a magnetic material. Data was
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stored by magnetising small regions on the drum's surface. The drum would rotate
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at high speeds and read/write heads were positioned along the length of the drum
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to access data.
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Seen as a improvement on Williams Tubes and
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[delay line memory](Delay_line_memory.md) but superseded by magnetic core memory
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later. It's concept lived on in harddisk drives which became the dominant form
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of secondary storage.
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It had a larger capacity than the technologies that preceded it and it was also
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non-volatile - the data would remain intact when the power was turned off.
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It was used in the [IBM 650](The_History_of_Computing_Swade.md) (1953) and
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Ferranti Mark I (1951)
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