Nokia Lumia 830 - Display the notifications screen / Action Centre

If you want to display the Action Centre, which is basically a quick access notifications screen (similar to Android), then simply swipe your finger down from the top of the screen.

This will give you access to Airplane mode, Bluetooth, Wi-Fi, Rotation Lock and so on.

You will also see phone notifications which can be discarded by swiping your finger to the left or right.