The Karma system is an important feature in Fallout's gameplay. A player's actions, including conversation and combat choices, affects the player's status in the game world; a player who makes good decisions is received thêm positively bởi non-player characters, and a player that makes bad decisions has the opposite reaction. Crimes can also be committed bởi a player, and whichever faction hoặc group that is harmed bởi a crime are fully aware of the player's action in most cases. Other factions that were not affected bởi the crime will not be aware of it, and since a town is usually its own faction, news of a crime committed in one town will not spread to another. Beware however, good hoặc evil deeds will cause a bounty bởi the opposite alignment group. Talon Company (If bạn are good) hoặc the Regulators (if you've been bad) will ambush bạn randomly, and are not bound to any particular area, they can appear anywhere in the wastes. Factions can range in size and boundaries, however, and may not be restricted to a single area. The game world itself was planned to be significantly smaller than that of Oblivion's but is now similar in size.[2]