( 1950 ) Jay Forrester of MIT came up with the idea of using toroids or magnetic cores as the basic element of main memory in 1950.

The basic operating mechanism was to send an electric current along a wire threaded through the core. This produced a controlled magnetization of the core according to the hysteresis cycle. Each core stored one bit of information. They were normally organized in 64 × 64 to 128 × 128 planes (4 kbit to 16 kbit memories). The number of planes depended on the bits in the word (usually 16 to 32). The set of planes was called stack.

The ferrite core is the logo of the UPM’s schools and colleges of informatics.

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