Notifications
Notifications is a little box that popus up telling you something. You can ge to them by pressing this icon: If you have notifications then a number will apperar instead of the notificcation symbol.
Notifications pop up when you do something like when you take a screenshot, a timer ends, or when someone sends you a Google Web-based Software.
Settings
Settings
When you click on settings after you click notifications this will appear.
You can check the boxes with the ones you want to pop up as notifications.