Apple Disk Image
The icon depicts an internal hard drive within a generic file icon. | |
| Filename extension |
.dmg, .smi, .img |
|---|---|
| Internet media type |
application/x-apple-diskimage |
| Uniform Type Identifier (UTI) |
|
| Developed by | Apple Inc. |
| Type of format | Disk image |
Apple Disk Image is a disk image format commonly used by the macOS operating system. When opened, an Apple Disk Image is mounted as a volume within the Finder.
An Apple Disk Image can be structured according to one of several proprietary disk image formats, including the Universal Disk Image Format (UDIF) from Mac OS X and the New Disk Image Format (NDIF) from Mac OS 9. An Apple disk image file's name usually has ".dmg" as its extension. A disk image is a compressed copy of the contents of a disk or folder. To see the contents of a disk image, one must first open the disk image so it appears on the desktop or in a Finder window.