I've got a serious question (since a few days ago my bankroll exceeded $1000 and now i'm a serious player

).
It's a common occurrence that i see the expression "to outplay postflop" at 2+2 and other boards. so what exactly does that mean? to put the opponent on hand and get the maximum value of it, if you think you're ahead & avoid losing much in case you're behind? or something more?
And to your mind, what are the main postflop skills besides hand reading?
p.s. sorry for possible mistakes