Documentation for JIRA 5.1.x. Documentation for other versions of JIRA is available too. 
The following pages contain information on key concepts in JIRA:
Overview
Content Tools
Apps
See our Getting Help page for details.
Raise an issue for our developers.
See answers from the community.
Tweet, blog and update our documentation.
Except where otherwise noted, content in this space is licensed under a Creative Commons Attribution 2.5 Australia License.