If its a not private space e.g living room/dinning room etc - then what ever you want/maybe into a wall to maximize space...but private space eg bedroom/bathroom - as said above its the norm for it to maintain privacy to the last min so depending on room layout it may be the left or the right - but as an example - if you walk into a room and a parallel wall is on the left and the room "space" is on the right eg the bed then the door would be hinged on the right side so that you cant see that space till the last min/door fully open - giving the person half naked inside the time to shout at you!