I've watched it and I still don't fully understand it. Curling is kinda like shuffleboard, on ice. Players slide stones on the ice towards a target area which is segmented into four concentric circles. Two teams, each with four players, take turns sliding heavy, polished granite stones, also called rocks, across the ice - and the purpose is to accumulate the highest score by resting your stones closest to the center of the rings.
What I do know is Team USA hasn't been very good at it. Until now! John Shuster and his team scored five points in a huge 8th end to swing the momentum on the way to a 10-7 defeat of Sweden for the U.S.'s first ever curling gold medal.