Facebook is a social networking website which allows members to talk communicate and interact with other people digitally, as well as play games and assorted other activities. Facebook appears as the prime subject of the Season Fourteen episode, "You Have 0 Friends".
When Stan Marsh is the only member of the boys to not have a Facebook page and his friends bring it upon themselves to create a Facebook page for him. The unwilling Stan suddenly finds himself barraged by his friends, family, and even his girlfriend, Wendy Testaburger, into using his Facebook page, despite his persistent notions that he wants nothing to do with it. Despite Stan being the least interested in keeping up with Facebook, he finds that his page has become one of the most popular pages on the network. This doesn't matter to him, and finally fed up with constantly being insulted and abused and bullied, he opts to simply delete his account.
Facebook, however, won't let that happen. The massive amounts of attention that Stan's page has received, has allowed it to become sentient. In order to maintain its control, Facebook digitally kidnaps Stan and draws him into a digital universe, in hopes that Stan will be destroyed during the great game of Yahtzee.
Stan however defeats his Facebook profile, allowing him to return to the real world and delete his account. He transfers all of his Facebook friends to Kip Drordy, whose lack of popularity was apparently social suicide for anyone who be-friended him, as Kyle Broflovski discovered.
Facebook reappears (although unnamed) in The Stick of Truth, where it serves as the player's main hub, where they can access their inventory and see recently given quests.
Aspects of Facebook
FarmVille is a parody of a Facebook farming game of the same name, in which players are allowed to plant and harvest crops, feed animals, and make friends if somebody else is on the farm.
This game became something of an addiction for Kyle, who upon losing all his friends, had to essentially beg Stan into 'friend-ing' him and play the game so Kyle's farm would continue to thrive.
When Stan is sucked into Facebook, he is able to travel to Kyle's FarmVille game so as to communicate with him, demanding help on how to get out.
Yahtzee is a game in which players must throw dice and try to get all of the dice to six. If the player manages to accomplish that, they are considered the winner.
While introducing Stan to the "joys" of Facebook, Kyle explains that the original game was adapted to Facebook, in a digital format to where players can play the game with other members online. Stan of course is less than impressed with the idea, finding Yahtzee rather dull to begin with.
When Stan is literally sucked into Facebook through his web-cam, he finds himself being forced into playing Yahtzee in order to survive within the digital world. His first game is against a random player, who is then 'deleted' upon his defeat, and then against his sentient Facebook profile. Both times, he is victorious with one roll of the dice.
Taking it upon himself to "help people make friends", Cartman creates a series of podcasts called Mad Friends, where he reports friend numbers similar to a stock market and gives advice on who to "friend" and who to remove.
Stan came across the podcast after being bullied into updating his Facebook page. The video he watched involved Cartman taking shots at Kyle and convincing everyone to de-friend him due to his friendship with Kip Drordy. Cartman's podcast apparently has a high-viewership, as Kyle soon found himself with only Kip as a Facebook friend. Cartman also urges kids to "Friend" Clyde Donovan, as his Birthday is coming up, and his mother intends to take Clyde and his friends to Casa Bonita. Cartman's behavior and podcast is a parody of Jim Cramer, the host of CNBC's Mad Money.