Ok, first off, if you knew these, don't rant on me. I'm just sharing for other people to know.
Now, to tell you something. In Minecraft, there are some non-configurable controls. Most non-configurable controls use the function keys (F) (The function keys are normally on the top of your keyboard). Some are useful, others are just there for more hardcore players. So, here they are...

F1 - Toggle HUD
F2 - Take a screenshot that it placed in /.minecraft/screenshots
F3 - Shows your seed, coordinates, memory your using, some other technical schtuff
F4 - Nothing (NOTHING!)
F5 - Toggle 3rd person mode, your face (No really) and 1st person (Default)
F6 - Same as F4 (NOTHING!)
F7 - Same as F6 (NOTHING!)
F8 - Turns on smooth camera. Your camera view becomes smooth, cinematic, useful for making Minecraft movies.
F9 - Same as F7 (NOTHING!)
F10 - Buggy. Don't use...
F11 - Toggle fullscreen mode
F12 - Same as F9 (NOTHING!)

NB! A lot of laptops have other things for function commands to do, such as sound or brightness. To use these function controls on those keyboards, try holding (fn). If it still doesn't work, call your mom. JK.

So there you have it! All the function controls!

If you knew these controls, give a diamond so newbies to the game will see this.
If you didn't know these controls, give a diamond cause' you learn't something new!