ARJ

File Format
Name	ARJ
Ontology	Electronic File Formats Archiving ARJ
Extension(s)	.arj
PRONOM	fmt/610

Overview

ARJ was one of the leading compression tools during the nineties. While it was a bit slower than PkZIP, it sported many more options, some of which were unique during that time (archives over multiple disks/volumes, fine-tuning of the compression algorithms used based on the data that was being compressed, recovery records to recover from simple transmission errors, etc.)

Software

• Official homepage of ARJ software
• 7-Zip
• Open-source ARJ

Sample files

• http://cd.textfiles.com/20mnn/HPTEXT/PHRACK/
• The Silver Collection CDs have many ARJ files

Resources

• Wikipedia article
• Page on fileformat.info[1]
• Another, slightly more verbose, file format description[2](apparently moved here)