Linear is a word used to describe a games path of progression. Linear means the path does not branch - players go down a straight line, usually from level-to-level or map-to-map. Any of your actions will not change what you do next, meaning you have no option to where you'll go next. Some games may be partially linear due to side quests. Gamers tend to prefer non-linear storyline and progression, but the linear style still has it's place. Real-time strategy games tend to favor linear advancement.