A level, map, area, stage, world, track, board, floor, zone, phase, mission, episode, or course in a video game is the total space available to the player during the course of completing a discrete objective. Video game levels generally have progressively increasing difficulty to appeal to players with different skill levels.^[1] Each level presents new content and challenges to keep player's interest high.^[1]

In games with linear progression, levels are areas of a larger world, such as Green Hill Zone. Games may also feature interconnected levels, representing locations.^[2]

Level design or environment design is a discipline of game development involving creation of video game levels—locales, stages, or missions.^[3][4][5][6] This is commonly done using a level editor, a game development software designed for building levels; however, some games feature built-in level editing tools. Level design is both an artistic and technical process.^[7]

A bonus stage (also known as a bonus level or bonus round) is a special level within a video game designed to reward the player or players, and typically allows the player to collect extra points or power-ups. Bonus stage either have no enemies or hazards, or replace the normal penalties for being struck by enemies or hazards with simply being thrown out of the bonus stage. Many bonus stages need to be activated or discovered in some manner, or certain conditions must be satisfied to access them. Otherwise, they appear after the player has completed a certain number of regular stages.^[8]