It might be necessary to stop a running task before it terminates regularly. This can be done manually via Icon / Toolbar) or as instruction from a running task. Assuming there is an endless loop working with two DVD Players. Now the DVD Player are needed for some other action, but it is impossible to use them as long as the endless loop is running, because they are blocked. With the StopTask command it is possible to terminate the endless loop and then use the DVD Players in another task.
The command is available via main menu Insert → Stop Task or the Script Editor's context menu. That opens the Task Selector presenting all tasks (Cuelists and Scripts). Choose the task that has to be stoped.