Not necessarily. You can have it after workout, you can have it before workout. I personally eat a solid meal after workout and didn't see ay difference. When i use protein powders, i have them like meal's, it can be any given meal of the day.
Some will claim faster acting proteins than isolate, like whey/casein hydrolysate or BCAA's are much better. In my opinion, it really doesn't matter again and it's mostly a marketing scam. What really matter is make sure you get adequate protein at the end of the day, whether post/pre/breakfast/dinner or powder/meat/eggs
If you're concerned about post /pre / intra workout nutrition, make sure you get carbs as well as protein.