Definition

Noun: 1. A small ferrite ring used historically in computer memory: A "magnetic core" is a tiny, doughnut-shaped piece of ferrite (a magnetic ceramic material). It was a fundamental component in early random-access memory (RAM) systems for computers, where each individual core could store one single bit of digital data (a 0 or a 1) based on its direction of magnetization. 2. The central, often magnetic, part of a component: More generally, in electrical engineering, a "magnetic core" can refer to the central piece of magnetic material around which wires are coiled in components like transformers, inductors, or electromagnets, used to concentrate and guide the magnetic field.

Usage Examples

• Noun (Computer Memory):
  • Early mainframe computers relied on arrays of magnetic cores for their main memory.
  • The state of a single bit was determined by the magnetization direction of one magnetic core.
• Noun (Electrical Component):
  • The transformer's efficiency depends heavily on the material of its magnetic core.
  • An inductor typically consists of a coil of wire wound around a magnetic core.

Advanced Usage

• "Core memory" or "core storage": This refers to the complete memory system constructed from a grid or plane of many individual magnetic cores.
  • The Apollo Guidance Computer famously used core memory for its robustness.

Variants and Related Words

• Core (n): In computing contexts, "core" is often used as a shortened, informal form of "magnetic core" when discussing historical memory technology.
  • The program was loaded into the machine's core.
• Ferrite core (n): A more specific term highlighting the common material used, especially for high-frequency applications.
  • The noise filter uses a ferrite core on the cable.

Synonyms

• Memory core (n): Specifically when referring to its use in computer memory.
• Toroidal core (n): Describes the characteristic ring (torus) shape.

Related Phrases

• Core dump (n): While a modern term, its origins lie in this technology. It originally referred to printing or saving the literal contents of "core memory" for debugging.
• Core rope memory (n): A related, read-only memory technology that also used magnetic cores in a different configuration.

Noun

1. (computer science) a tiny ferrite toroid formerly used in a random access memory to store one bit of data; now superseded by semiconductor memories
   • each core has three wires passing through it, providing the means to select and detect the contents of each bit