What is core memory?

Core memory, also known as magnetic core memory, is an early form of computer memory. It was first introduced in the 1950s and used in many computer systems until the 1970s.

Core memory works by using tiny magnetic cores that are electromagnetically charged to store information. These cores are made of a material such as ferrite and are arranged in a grid pattern. The cores can be magnetized in two different directions, representing binary states 0 and 1.

A read-write head would be used to read or write data on the memory. It would send an electrical pulse to a specific core, magnetizing it either clockwise or counterclockwise, thereby storing a bit of data. To read the data, the read-write head would send another pulse to the core, which would induce an electrical signal in the head. This signal could then be interpreted as either a 0 or a 1.

Core memory was considered to be very reliable and durable, as it had no moving parts. However, it was also relatively slow compared to modern memory technologies and was eventually replaced by faster and more efficient types of memory.