POWER LEVELING, What is this?

So i see a lot of this Power Leveling in the forums and i was wondering what it was???

It’s when a player of a low level joins a higher level player’s game and the higher level player completes quests and kills enemies. The higher level player will get a bit of xp but the lower level player will get a lot, resulting in an easy way to gain level ups.

Oh, Nice…