Welcome to Cards of Lunacy. Essentially this is just an online version of Cards Against Humanity(tm) that lets you play with your friends in realtime using Websockets.
There are two decks of cards, a white deck and a black deck. Each person gets 10 white cards and will have 10 white cards until the deck runs out or cards. One black card is taken from the black deck and placed up so that everyone can see. Everyone but the one judging the round will place down what he or she thinks matches the black card the best. The judge that will be selected from the players in your room will pick a white card that best matches the black card. After the card is picked the player that put the white card will gain a point. The person at the end of the game with the most points is the winner.
This game is much like Apples to Apples(tm) but is geared towards adults and has very offensive cards. If you are easily offended by anything in particular this game may not be for you.