Letter: J
- jabberd - OpenSource server implementation of the Jabber protocols
- jack-audio-connection-kit - The Jack Audio Connection Kit
- jack-audio-connection-kit-devel - Header files for Jack
- jack-audio-connection-kit-example-clients - Example clients that use Jack
- jakarta-commons-cli - Command Line Interface Library for Java
- jakarta-commons-cli-javadoc - Javadoc for jakarta-commons-cli
- jam - Program construction tool, similar to make
- jasper - Implementation of the JPEG-2000 standard, Part 1
- jasper-devel - JPEG-2000 library developer files
- javastroke - Optional java files
- javasvn - Pure Java Subversion client library
- javasvn-javadoc - Javadoc for JavaSVN
- jd - A 2ch browser
- jed - Fast, compact editor based on the S-Lang screen library
- jeta - Horde Java SSH module
- jfbterm - Japanese Console for Linux Frame Buffer Device
- jhead - Tool for displaying EXIF data embedded in JPEG images
- jigdo - Ease distribution of large files over the Internet
- jikes - Java source file to bytecode compiler
- jlint - Java program checker
- john - John the Ripper password cracker
- jomolhari-fonts - Jomolhari a Bhutanese style font for Tibetan and Dzongkha
- js - JavaScript interpreter and libraries
- js-devel - Header files, libraries and development documentation for js
- jthread - JThread provides classes to make use of threads easy on different platforms
- jthread-devel - Development files for JThread