That post was "resteemed." Someone else wrote it, I upvoted & resteemed it with this account because it was interesting, and due to the flags on what I deemed a high-quality post I brought GGG in to upvote and resteem as well. GGG will receive a small sum of Steem Power for its support, but it has so little voting weight that this reward will be negligible.

The more you "power up," the more your vote boosts the payout on other posts, and the more reward you get for supporting things. There are other factors at play, but that's the rough mechanism.