One little annoyance about the OSX Screen is the constant display of Menu’s and the dock, auto hiding the dock has always been possible but until el capitan you couldn’t hide the menu bar without going fullscreen.

well one free option is MenuAndDockless2.0 there are versions for other osx versions. the one thing to remember is ctrl alt cmd , (comma) this will bring up an interface to customise how you want an application to appear it also handles snapping left & right with ctrl alt cmd l and ctrl alt cmd r.

https://www.macupdate.com/app/mac/36314/menuanddockless/download

The manual can be found here