Upwords (also branded as Scrabble Upwords in the United States and Canada, and Topwords Crucimaster, Betutorony, Palabras Arriba, Stapelwoord in other countries) is a board game invented by Elliot Rudell and originally published by the Milton Bradley Company, now a division of Hasbro.
 The game remains under license to Hasbro by Rudell Design, LLC.
 Upwords is similar to "Scrabble", or "Words With Friends", in that players build words using letter tiles on a gridded gameboard.
 The point of difference is that in Upwords letters can be stacked on top of other letters already on the gameboard to create new words.
 The higher the stack of letters, the more points are scored.
 This typically makes words built in later turns of the game more valuable than earlier words, increasing play intensity and adding a level of strategy unique to Upwords.
 The memorization of two-letter words is considered a useful skill in this game.
Ghettopoly is a parody of "Monopoly" released in 2003.
 Invented by David Chang, it uses "Monopoly"-like mechanics in the atmosphere of a caricaturized United States ghetto.

Question: Upwords and Ghettopoly, are both forms of what?
Answer: board game