A core equal to the head of an alpine is a ring-like ring made of magnetic material. The initial memory of a computer may contain several thousand such cores. It is possible to store a single core bit by magnetic field. The direction of the magnetic field created in the core depends on the electric current flowing through the core. If the magnetic field created for the flow of electricity on one side of the core of the core is taken to be the state of bit-0 protection , then the reverse magnetic field for the flow in the opposite direction is taken to be the state of bit-1 protection.