A release roadmap is the plan for future releases, which includes their schedules and planned issue sets.

A release history is simply the log of completed releases with their release dates and their fixed issues sets. This is what you see at the bottom of the release list after you select the Show released checkbox.

The default workflow for releases is minimal; however, you can implement more complicated workflows to manage your releases. Default release workflows include regular tracker workflows. For more information about using and configuring workflows, see Tracker Workflow.