In lots of games there are bugs, most the time they are annoying, or make it so all your hard work goes to waste as you can no longer beat the game because the npc you needed to talk to walk off the face of the earth and can't be found. However, some games have bugs that help you out, like Fallout 3's new expansion which allows you to steal weapons that never loose condition. Now I know lots of online games have bugs that help the person exploiting but makes everyone else hate them, so try to not mention bugs that make others hate people who use them 