ARC (compression format)

ARC was, at one point (1985-89), the leading file archiving and compression utility in the BBS world, replacing earlier utilities which generally only did one of the two functions (either combining multiple files in one file for convenient download, or shortening the file length to take less download time and disk space). Combining the two functions in one program simplified the process of preparing files for download and extracting them at the other end, leading to a rapid rise in popularity for the program (also called ARC, from System Enhancement Associates, a company run by Thom Henderson, who was very active in FidoNet). However, there was an equally rapid decline in its popularity following a lawsuit by SEA against rival Phil Katz, whose PKARC and PKXARC programs were compatible with the ARC file format, but were successfully sued for copyright and trademark violation. This was largely regarded by the BBS community as being a "David vs. Goliath" case of a faceless corporation bullying a "little guy", though in fact both companies were small, home-based operations. Nevertheless, the fallout from the suit led to rapid adoption of the competing ZIP format, introduced by Katz in 1989, and ARC files are no longer commonly encountered.

The fact that archives from an early period of BBSing are often in this format encourages bad puns referring to those who trawl such old archives as "Raiders of the lost ARC."

Identifiers

 * File extension: .ARC
 * MIME type (Internet media type): Has no specific registered type; generic binary application/octet-stream is generally used, or perhaps unregistered custom types with an x- prefix
 * Uniform Type Identifier (Apple): public.archive.arc