# auxiliary memory

> non-volatile memory that is not directly accessible by the CPU, instead being accessed via input/output channels

**Wikidata**: [Q2067979](https://www.wikidata.org/wiki/Q2067979)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Auxiliary_memory)  
**Source**: https://4ort.xyz/entity/auxiliary-memory

## Summary
Auxiliary memory is a type of non-volatile computer storage that is not directly accessible by the CPU. Instead, it is accessed via input/output channels, serving as additional storage space for information that can be copied into the processor when required. This form of memory is crucial for retaining data persistently, even when the power is off.

## Key Facts
*   Auxiliary memory is non-volatile, meaning it retains data without power.
*   It is not directly accessible by the CPU, requiring access via input/output channels.
*   Aliases include storage, computer storage, secondary storage, online storage, Memoria auxiliar, Memoria externa, Memoria masiva, Memoria secundaria, 補助記憶, and ストレージ.
*   It is classified as a type of computer memory or storage, and a subclass of recording medium and computer storage media.
*   In the memory hierarchy, auxiliary memory follows computer memory and is followed by nearline storage.
*   It functions as a backing store, providing additional storage space for information.
*   An example image is available at `https://commons.wikimedia.org/wiki/Special:FilePath/35-Desktop-Hard-Drive.jpg`.
*   The entity has a sitelink count of 17.

## FAQs
### Q: What is auxiliary memory?
A: Auxiliary memory is non-volatile computer storage that is not directly accessible by the CPU. It is accessed through input/output channels and provides additional storage for data that can be loaded into the processor when needed.

### Q: How does auxiliary memory differ from computer memory?
A: Auxiliary memory is non-volatile and not directly accessible by the CPU, requiring I/O channels for access, and is used for additional storage. In contrast, computer memory is a physical device used to store information for immediate use in a digital electronic device, implying direct CPU access for rapid operations.

### Q: Is auxiliary memory volatile or non-volatile?
A: Auxiliary memory is non-volatile, meaning it retains stored information even when the power supply is removed.

### Q: What are some other terms for auxiliary memory?
A: Other terms for auxiliary memory include storage, computer storage, secondary storage, online storage, Memoria auxiliar, Memoria externa, Memoria masiva, Memoria secundaria, 補助記憶, and ストレージ.

### Q: What is auxiliary memory's place in the memory hierarchy?
A: In the memory hierarchy, auxiliary memory follows computer memory, which is used for immediate data, and is itself followed by nearline storage, an intermediate type of data storage.

## Why It Matters
Auxiliary memory is fundamental to modern computing because it provides the essential capability for persistent data storage. Unlike volatile computer memory, which loses its contents when power is removed, auxiliary memory retains information indefinitely. This non-volatile nature is critical for storing operating systems, applications, user files, and any data that needs to be preserved across power cycles. Its design, which involves accessing data via input/output channels rather than directly by the CPU, allows for significantly larger storage capacities at a lower cost compared to primary memory. This enables computers to store vast amounts of information, from personal documents to large databases, making it possible for users to save their work, install complex software, and access a wealth of digital content. Without auxiliary memory, computers would be unable to retain any information once powered off, severely limiting their utility and making them impractical for most applications. It serves as the long-term repository for all digital data, bridging the gap between immediate processing needs and permanent data retention.

## Notable For
*   **Non-Volatile Nature**: It retains data even when power is removed, distinguishing it from volatile computer memory.
*   **Indirect CPU Access**: Unlike primary memory, it is not directly accessible by the CPU, instead relying on input/output channels for data transfer.
*   **Role as Backing Store**: It serves as a primary location for additional storage space, holding information that can be copied into the processor as needed.
*   **Position in Memory Hierarchy**: It occupies a specific place in the memory hierarchy, following computer memory and preceding nearline storage.
*   **Enabling Persistent Storage**: It is crucial for the long-term storage of digital data, making computers practical for saving and retrieving information.

## Body
### Definition and Characteristics
Auxiliary memory is defined as non-volatile memory that is not directly accessible by the CPU. Its access is facilitated through input/output channels, distinguishing it from memory directly connected to the CPU. This characteristic allows it to function as a backing store, providing additional storage space for information that can be accessed and referred to when required, and copied into the processor if needed. It is designed for persistent data retention.

### Classification and Relationships
Auxiliary memory is classified as a type of computer memory or storage. It is a subclass of both recording medium and computer storage media.
Within the memory hierarchy, auxiliary memory has specific relationships:
*   It `follows` computer memory, which is used for immediate data processing.
*   It is `followed by` nearline storage, an intermediate type of data storage that balances frequent access with long-term storage.

It is also related to `magnetic storage`, a method of storing data on a magnetized medium, which has an inception date of 1878.

### Associated Storage Types
Auxiliary memory is associated with several broader categories of storage:
*   **Computer storage media**: The general class for storage of digital data readable by computers.
*   **Direct-attached storage**: External computer storage accessed directly by a single host over a local computer bus and/or interface.
*   **Backing store**: A computer storage device, typically a disk, that offers supplementary storage space for information.
*   **File storage**: A general type of storage.

### Aliases
Auxiliary memory is known by several aliases, including:
*   storage
*   computer storage
*   secondary storage
*   online storage
*   Memoria auxiliar
*   Memoria externa
*   Memoria masiva
*   Memoria secundaria
*   補助記憶
*   ストレージ

### Identification and References
*   **Wikipedia Title**: Auxiliary memory
*   **Wikipedia Languages**: ca, da, de, en, es, et, ga, ja, nl, no
*   **Wikidata Description**: non-volatile memory that is not directly accessible by the CPU, instead being accessed via input/output channels
*   **Google Knowledge Graph ID**: /g/1q6kyn5vy
*   **Gran Enciclopèdia Catalana ID**: memoria-auxiliar (and former scheme: 0193698)
*   **Dictionary of Archives Terminology ID**: online-storage
*   **Encyclopedia of China (Third Edition) ID**: 39128

```json
{
  "@context": "https://schema.org",
  "@type": "Thing",
  "name": "auxiliary memory",
  "description": "Non-volatile memory that is not directly accessible by the CPU, instead being accessed via input/output channels.",
  "sameAs": [
    "https://en.wikipedia.org/wiki/Auxiliary_memory",
    "https://www.wikidata.org/wiki/Q1333038"
  ],
  "additionalType": "https://schema.org/ComputerStorage",
  "image": "https://commons.wikimedia.org/wiki/Special:FilePath/35-Desktop-Hard-Drive.jpg",
  "alternateName": [
    "storage",
    "computer storage",
    "secondary storage",
    "online storage",
    "Memoria auxiliar",
    "Memoria externa",
    "Memoria masiva",
    "Memoria secundaria",
    "補助記憶",
    "ストレージ"
  ]
}

## References

1. Quora