28 lines
		
	
	
	
		
			1,019 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			28 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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								# 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								[delay line memory](Delay_line_memory.md) but superseded by magnetic core memory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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