J
J/K - Just Kidding
Jabber
Jack
JAM - Just A Minute
JANET - Joint Academic NETwork
JAR
JAR
JAS - Just A Second
Java
Java VM - Java Virtual Machine
JavaBeans
JavaScript
JAZ
JBOD - Just a Bunch Of Drives
JCL - Job Control Language
JDBC - Java Data Base Connectivity
JDF - Job Definition Format
JEDEC - Joint Electronic Device Engineering Council
Jitter Correction
JMS - Java Message Service
Join
Joliet
Joy, Bill
Joystick
JP2
JPEG - Joint Photographic Expert Group
JPEG2000 - Joint Photographic Experts Group 2000
JPG
JSP - Java Server Page
JTAG - Joint Test Action Group
Jumper - Ponticello
Junk mail
Just link
Just-in-time
JVM - Java Virtual Machine
Jython