The new Mac Book Pro (2016 / 2017?) now has this thing called a “touch bar”. It replaces all the function keys (F1, F2, etc.) with a touchable display. Keys display on the touch bar based on application context. It is actually quite nifty, however, in some applications I always want the function keys to display.
To always display function keys for certain applications, go to Keyboard Preferences --> Shortcuts











