How to turn off the floating app on my iPhone 5?

Yesterday, something appeared on my phone that looks like a small, faint moon that I can drag around to anywhere on the screen. When I tap it, it brings up quick menus that I can use to pick various functions. It's kinda cool but I need it to go away. Unfortunately, I don't see how to get rid of it. It stays in whatever spot I move it to regardless of what is on the screen (e.g.address book, phone, Netflix, You Tube, home page, etc.). What is it and how did it get there?

Go to settings > general > accessibility > and turn off assistive touch