The feromagnetic core can hold binary information by being magnetised with a pulse of current in the lead W in one or the other remanent state (b+, b-). Due to the perpendicular hysteresis loop of ferite, the core remains in the current state if magnetic field caused by the pulse is weaker than Hm.

Core memory has the cores entwined in a net, that makes one plane. More of these can be stacked one above another into a block. The number of cores in a plane determines the number of words and the number of planes determines the length of words.

Pictures taken from: Elektronski ra?unalniki, ve? avtorjev, Elektrotehni�ka zveza slovenije, Ljubljana 1971