So, one of the interetings things when working with a tasks, is to see it's activity.
What has happened with the task, who has done what, when etc.
The easiest way to see a task activity is to

  1. Click on a task to open it.

  2. To the left click on the activity tab

  3. On the right, then you will be able to see all activity that has occured inside this task.