A task will have a specific status depending on whether the material is activated or not, and where the assigned user is with completing it.  The following are the available statuses each task may take on through its lifecycle:

Pending - The material for this task is in a "paused" status, once its set to "active" it will automatically create a task for the user and change the status to "assigned"

Assigned - A task that has been given to a user that they have not started

In Progress - A task given to a user that has been started but not completed

Pass/Fail - A task that the user passed or failed

Closed - An unfinished task that was marked as no longer necessary (e.g. recipient was removed) and can no longer be worked on.