An archive format for the IBM PC. ARJ
files are handled by the ARJ program, created by the American
programmer Robert Jung.
A compression program for backup archiving from ARJ Software, Inc., Norwood, MA (www.arjsoftware.com). Introduced in the early 1990s and created by Robert Jung (the RJ in ARJ), ARJ never achieved the popularity of PKZIP, although it is considered a worthy competitor. See JAR.