# magnetic-core memory

> predominant form of random-access computer memory for 20 years between about 1955 and 1975

**Wikidata**: [Q839647](https://www.wikidata.org/wiki/Q839647)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Magnetic-core_memory)  
**Source**: https://4ort.xyz/entity/magnetic-core-memory

## Summary
Magnetic-core memory was the predominant form of random-access computer memory for approximately 20 years between about 1955 and 1975. This technology served as the primary RAM in early computers before being replaced by semiconductor memory.

## Key Facts
- Magnetic-core memory dominated random-access memory technology from about 1955 to 1975
- It is a subclass of random-access memory with 31 Wikipedia sitelinks
- Related technologies include thin-film memory and the Soviet Memory Cube series
- The 290 series and 263 series integrated circuits were developed specifically for core memory applications in Soviet computers
- Images of magnetic-core memory are available through Wikimedia Commons
- The technology has various aliases including core memory, magnetic core, and core

## FAQs
### Q: When was magnetic-core memory commonly used in computers?
A: Magnetic-core memory was the predominant form of random-access computer memory for approximately 20 years between about 1955 and 1975.

### Q: How is magnetic-core memory related to other memory technologies?
A: It is related to thin-film memory which used 4 µm thick dots of permalloy on glass plates, and the Soviet Memory Cube series which began in 1962. The 290 series and 263 series integrated circuits were developed for core memory readout and I/O interface.

### Q: What are alternative names for magnetic-core memory?
A: Magnetic-core memory is also known as magnetic core memory, core memory, magnetic core, core, and has various Spanish translations including memoria de nucleos magneticos, memoria de nucleo magnético, and memoria de núcleo magnético.

### Q: Where can I find more information about magnetic-core memory?
A: Information is available on Wikipedia in multiple languages (ar, bg, ca, cs, da, de, en, es, et), the National High Magnetic Field Laboratory's website, and museum digital collections with tag ID 115930.

## Why It Matters
Magnetic-core memory represents a critical era in computing history when random-access memory was transitioning from unreliable vacuum tube technology to solid-state electronics. For two decades, this technology served as the backbone of computer memory systems, enabling the development of more sophisticated computing applications that laid the groundwork for modern computing. Its reliability and non-volatility (data retention without power) were significant advantages over earlier technologies, making it essential for both military and commercial computing systems during the 1950s, 60s, and early 70s. Understanding magnetic-core memory provides insight into the evolution of computer architecture and the challenges engineers faced in developing reliable memory systems.

## Notable For
- Dominated random-access memory technology for two decades (1955-1975)
- Featured specialized Soviet implementations including Memory Cube modules
- Required custom integrated circuits like the 290 series for readout amplification
- Maintained data retention without power (non-volatile) operation
- Represented a significant improvement in reliability over earlier memory technologies

## Body
### Technical Specifications
- Images available from Wikimedia Commons showing close-ups of core memory modules (8k x 12 bit H-212 configuration)
- Related to thin-film memory which used 4 µm thick dots of permalloy deposited on glass plates
- Soviet Memory Cube series began in 1962 according to museum documentation
- The 290 series integrated circuits were hybrid amplifiers specifically designed for core memory readout in Soviet computers

### Classification and Documentation
- Subclass of random-access memory
- GND ID: 4163631-4
- Freebase ID: /m/0kdvp
- WordNet 3.1 synset ID: 03112720-n
- Microsoft Academic ID (discontinued): 2780337100
- Encyclopædia Britannica online ID: technology/magnetic-core-storage
- Museum digital collection tag ID: 115930

### Language and Terminology
- Wikipedia available in: ar, bg, ca, cs, da, de, en, es, et
- English Wikipedia title: Magnetic-core memory
- Common aliases: magnetic core memory, core memory, magnetic core, core
- Spanish variants: memoria de nucleos magneticos, memoria de nucleo magnético, memoria de nucleo magnetico, memoria de núcleo magnetico, memoria de núcleo magnético

### Historical Context
- Described at the National High Magnetic Field Laboratory website with specific citations
- Soviet implementation included the 263 series integrated circuits for core memory and I/O interface
- Wikimedia Commons category: Core memory (linked to Q328)
- Brief but historically significant chapter in computer memory development lasting approximately 20 years