Amiga Disk File aka ADF is a file format used by Amiga computers and emulators to store images of disks. It has been around almost as long as the Amiga itself, although it was not initially called by any particular name. Before it was known as ADF, it was used in commercial game production, backup and disk virtualisation. Technically speaking, ADF is not really a file format but actually a track-by-track dump of the disk data as read by the Amiga operating system, and so the "format" is really fixed-width AmigaDOS data tracks appended one after another and held in a file. The Amiga is a family of home/personal computers originally developed by Amiga Corporation as an advanced game console. ... A file format is a particular way to encode information for storage in a computer file. ... AmigaOS is the default native operating system of the Amiga and AmigaOne personal computers. ...

Most ADF files are images of the Amiga-formatted tracks held on cylinder 0 to 79 of a standard 3.5" Double Density floppy disk, also called a 880KB disk in Amiga terms. The size of an ADF will vary depending on how many tracks have been imaged, but in practice it is unusual to find ADF files that are not 901120 bytes in size. A disk drive cylinder is a division of data in a disk drive, as used in the CHS addressing mode of a hard disk (or floppy disk). ... Double Density usually refers to a physical format in a magnetic storage system that uses twice as many bits per length unit as the basic format. ...

Most Amiga programs were distributed on Double Density floppy disks. There are also 3.5" High Density floppy disks which hold up to 1.76 MB of data but these are uncommon. The Amiga also had 5.25" Single Density disks. The WinUAE Amiga emulator supports all 3 disc formats but 3.5" DD is the most common. UAE (or UNIX Amiga Emulator) is a free software designed to run software written for the Amiga range of computers. ...

There is also an ADF file format called ADZ which is a Gzip compressed ADF file. gzip is short for GNU zip, a GNU free software replacement for the Unix compress program. ... There are several types of compression: physical compression data compression multimedia compression image compression executable compression audio compression video compression bandwidth compression audio level compression compression (functional analysis) See also Arch bridge Compression arch suspended-deck bridge Compressor Compression ratio This is a disambiguation page, a list of pages that...

The ADF file format can only store disks that have legal AmigaDOS format tracks. The Amiga's Floppy Disk Controller was very basic, but also very flexible. Disk handling is not completely locked down like the one in a modern PC, and so most of the work to read and write disks is done by the operating system itself. However, because programmers did not have to use the operating system routines, it was quite normal for games developers to create their own disk formats and also apply many different sorts of copy protection. As it was, most full-price commerical Amiga games had some form of custom disk format and/or copy protection on them. For this reason, most commerical Amiga games cannot be stored in ADF files, but there is an alternative called IPF (Interchangeable Preservation Format) which was specifically designed for this purpose. AmigaOS is the default native operating system of the Amiga and AmigaOne personal computers. ... A Floppy Disk Controller (FDC) is a special-purpose chip and associated circuitry that directs and controls reading from and writing to a computers floppy disk drive. ... One of the first PCs from IBM - the IBM PC model 5150. ...

There is a program called ADF Opus which is a Windows-based program which allows people to create their own ADF files. This program supports creating Double Density ( 880 KB ADF files. This is the most common) & High Density ( 1.76 MB ADF files). ADF Opus also allows people to convert ADF files into ADZ files. Microsoft Windows is a series of operating environments and operating systems created by Microsoft for use on personal computers and servers. ...