How do you use this Android feature?

I don't know what this feature is called or how it is being used. Firstly, what is the name of that icon marked in red to get to the screen in question? Example, the "wheel" is Settings, what is the other icon called?

When I tap on that icon, I get the screen shown below, I have all these icons, what are they for and how do I use them?

(I didn't want to tap on them without knowing what it is going to do, in case I cannot reverse the changes I made by tapping on those icons)

i.imgur.com/zNQo1m9.png

i.imgur.com/at2q8bX.png

— modified on May 11, 2015, 11:10:55 PM

Found the answer from Android Authority - Notification Panel for quick settings. That's what it was.