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Self-booting disk

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A PC booter, or booter, is a type of software for home computer era (early 1980s to early 1990s) personal computers that was loaded and executed in the bootup of the computer, from a bootable floppy disk, rather than as a regular program; a booter thus bypassed any operating system that might be installed on the hard disk of the computer. Video games were the type of application most commonly distributed as booters.

History

Some booters include a customized subset or variant of a "standard" operating system for the platform (for example, DOS for IBM PC compatible, Apple DOS or ProDOS for Apple II, etc.).

Amiga and Commodore 64 games were often distributed as bootable floppies using a custom boot block which would consist of a custom loader. These disks contained no filesystem; instead, the custom loader would read the tracks directly. Many Amiga games were released as such in order to thwart piracy, and to utilize the RAM otherwise occupied by the AmigaOS. In early to mid-1990s, disks with a custom boot block became very popular for making so-called "trackmos" by demo groups.

While booters provided a safe form of copy protection[citation needed], programs such as Locksmith and Copy II PC existed that provided a method for copying of these disks; these were known as nibble copiers.

Today, IBM PC compatible computers can still boot from floppies, CD-ROMs/DVDs, USB storage devices etc., if a corresponding drive is connected to the system. However, it may require to change boot device priority in the BIOS setup utility.

Benefits

  • Ease of use (the software would start automatically, without any further action required by the user).
  • Insulation (few chances to manually alter program files). In a way, the booter acted as a sandbox, even though the concept didn't exist yet.
  • Copy prevention (the booter floppies can be hard to read and copy with a regular operating system – mostly because they often used a nonstandard filesystem or formatting).
  • Bypassing the normal operating system (to use some specialized replacement).

The last benefit was critical for games, as it allowed to use specialized replacements such as lightweight filesystems and memory access.[citation needed] This allowed performance boosts, especially for graphical applications.[citation needed]

Drawbacks

  • The application cannot co-exist with other installed applications (because of the insulation described in the previous section).
  • Bypassing the normal operating system forced the developers to anticipate every hardware-related or driver-related issue. They would have to write drivers themselves. This could cause compatibility issues on unusual equipment.

See also