Timeline view means all your treatments shown are based on a specific time.
Task view allows you to view treatments, which are not based on time.
If you choose hybrid, this will allow seeing both the task and timeline views together.
How to switch between the different views:
On the iPad, you can switch between the different views from the "Settings" tab, and then a box will open to the left:
On the web you can also switch between the different views from the menu on the right of the whiteboard:
How to choose how your departments are displayed:You can access your 'Department' settings via your Account Settings, & then switch each department to any of the above-described views:
This will change the department view on both Web and iPad.