hide a program

Hi everyone, I am a complete MAC novice having just migrated after years and years of specialization in Windows. I am looking for a way or a program (free or not) that works like Taskbar Hide in Windows., in that, with a combination of keystrokes you can hide and unhide a RUNNING application...

Hi guys, I have a secondary screen connected which is mirroring my main screen. I would like to know if I can have an application only show on my main screen. I don't want to make the secondary screen an extended screen since I have to present something and during this presentation I have to...