# Raw disk image

> file format for files which store raw disk images of floppy disks, hard drives, or optical discs

**Wikidata**: [Q3146723](https://www.wikidata.org/wiki/Q3146723)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/IMG_(file_format))  
**Source**: https://4ort.xyz/entity/raw-disk-image

## Summary
A raw disk image is a file format that stores an exact copy of a disk's contents and structure, such as floppy disks, hard drives, or optical discs. It is commonly used for backups, virtualization, and preserving legacy systems, often identified by the `.img` file extension. This format provides a bit-for-bit representation of the original media, ensuring data integrity and compatibility.

## Key Facts
- **File Extension**: Primarily uses the `.img` extension.
- **Media Type**: Defined as `application/vnd.efi.img`.
- **Aliases**: Known as IMG or IMG (file format).
- **Instance Of**: A subset of the broader "disk image" category.
- **Language Support**: Wikipedia articles available in English, Spanish, French, Xhosa, and Chinese.
- **Wikidata ID**: Associated with the discontinued Microsoft Academic ID `126249665`.
- **Purpose**: Captures raw, uncompressed data for accurate disk replication.

## FAQs
### Q: What file extension is used for raw disk images?
A: Raw disk images typically use the `.img` file extension, though they may also be labeled as `IMG` files.

### Q: What is the primary use of a raw disk image?
A: Raw disk images are used to create exact copies of physical disks for backups, virtual machine booting, or preserving legacy software and operating systems.

### Q: How does a raw disk image differ from other disk image formats?
A: Unlike compressed or formatted disk images (e.g., `.iso`), raw disk images contain an uncompressed, bit-for-bit copy of the original disk, including all metadata and structure.

## Why It Matters
Raw disk images are critical for data preservation and system recovery. They enable users to replicate disks exactly, including boot sectors and file systems, which is essential for troubleshooting, virtualization, and running legacy software without original hardware. This format ensures compatibility across different operating systems and tools, making it a universal solution for archiving and deploying disk content. By maintaining a precise copy of the source media, raw disk images prevent data corruption and loss, addressing challenges in digital preservation and system deployment.

## Notable For
- **Uncompressed Accuracy**: Stores a bit-for-bit copy of the original disk, including unused space and metadata.
- **Cross-Platform Compatibility**: Recognized by most operating systems and emulation software.
- **Legacy Preservation**: Widely used to archive obsolete media (e.g., floppy disks) for historical or functional access.
- **Versatility**: Supports floppy disks, hard drives, and optical discs in a single format.

## Body
### Definition and Purpose
A raw disk image is a file format designed to store the complete, unaltered contents of a physical disk. This includes the file system, boot records, and all data sectors, creating a functional duplicate of the original media. It is distinct from formatted disk images (e.g., ISO 9660 for optical discs) by its lack of compression or structural interpretation.

### Technical Specifications
- **Structure**: Represents the disk as a sequence of bytes, mirroring the physical storage.
- **File Extensions**: Commonly `.img`, though variations exist (e.g., `.dsk` for some platforms).
- **Media Types**: Associated with `application/vnd.efi.img` for EFI system partitions.

### Applications
- **Virtualization**: Used to boot virtual machines with identical disk configurations.
- **Backup and Recovery**: Enables full system restoration from a single file.
- **Legacy Software**: Allows execution of old programs by emulating vintage hardware environments.

### Relation to Other Formats
- **ISO Files**: Unlike ISOs, which are optimized for optical discs, raw images apply to any disk type.
- **Compressed Images**: Tools like `.zip` or `.gz` may compress raw images for storage efficiency, but the base format remains uncompressed.

## References

1. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)