Core memory is a type of computer memory that uses magnetic cores to store data. Each core represents a single bit of information, either a 0 or a 1, and is threaded with wires to read and write data. This technology was widely used in early computers before the advent of more modern memory types. Developed in the 1950s, core memory was known for its durability and reliability. It allowed computers to retain information even when powered off, making it an essential component in early computing systems. Today, core memory is largely obsolete, replaced by faster and more efficient technologies like semiconductor memory.