magnetic drum

computing

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Last updated

June 30, 2026

Quick Summary

A magnetic drum was an early form of auxiliary data storage for computer systems. It operated similarly to tape and disk units, storing data as magnetized spots on the surface of a rotating metal cylinder.1

Magnetic Drum Operation

Data was stored in circular tracks on the drum's surface.1
A single drum could contain numerous tracks.1
Recording and reading of data were performed by heads positioned close to the drum as it spun at high speeds (around 3,000 revolutions per minute).1

While magnetic drums offered rapid, random access to information, retrieving data faster than tape and disk units, they had a lower storage capacity compared to those devices. Magnetic drums were used for data storage starting in the early 1950s.1

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magnetic recording
Other magnetic recording devices.
Such magnetic recording mediums as drums and ferrite cores have been used for data storage since the early 1950s. A more recent development is the magnetic bubble memory devised in the late 1970s at Bell Telephone Laboratories.
Read More
Such magnetic recording mediums as drums and ferrite cores have been used for data storage since the early 1950s. A more recent development is the magnetic bubble memory devised in the late 1970s at Bell Telephone Laboratories.
Read More

computer memory
Magnetic drum memory
Magnetic drums, which had fixed read/write heads for each of many tracks on the outside surface of a rotating cylinder coated with a ferromagnetic material, were used for both main and auxiliary memory in the 1950s, although their data access was serial.
Read More
Magnetic drums, which had fixed read/write heads for each of many tracks on the outside surface of a rotating cylinder coated with a ferromagnetic material, were used for both main and auxiliary memory in the 1950s, although their data access was serial.
Read More