Activity Hierarchy
On the left side of the Activity tab, the activity hierarchy is displayed. The hierarchy shows the activities you are permissible to see in alphabetical order. You use activities to describe your future plans and how they scale down to detailed actions.
Note
You may see different activities in this area than your colleagues. Which activities you have access to is determined by the administrators. Contact your system administrator if you have any questions.
If the width of the hierarchy area is too small or large for your tasks, hover the right border of the area with the cursor. The cursor display changes to 
and a light gray band is displayed for the border:
Drag-and-drop the border to the desired size.