reloading their last savegame. This allows for an indefinite winning streak. Game programmers may defend against savescumming by various means, such as checking timestamps. For example, on multiuser Unix systems, NetHack uses setgid to prevent users from copying save files into the necessary directory. Types of saved games Autosave Game saving does not need to be manual. Some video games save the game in progress automatically, such as after the pass of a fixed amount of time, at certain predetermined points in the game as an extension to the save point concept, or when the player exits. Some games only permit "suspend saves" in which the game is automatically saved upon exiting and reloaded upon restarting. The aim of a suspend save is only to allow the gameplay to be temporarily interrupted; as such, suspend saves are erased when the player resumes the game. This concept was popularized by Rogue and the namesake genre, which are known for employing the mechanic such that if the player were to die in the game, their save file is destroyed and the game must be restarted. The term "perma-death" would come to refer to the concept used for that purpose. It is possible to cheat the system by copying and reusing suspend save files in an act of what is considered to be a form of savescumming. Checkpoints "Checkpoints" are locations in a video game where a player character respawns after death. Characters generally respawn at the last checkpoint that they have reached. A respawn is most often due to the death of the in-game character, but it can also be caused by the failure to meet an objective required to advance in the game. Checkpoints might be temporary, as they stop working when the player loses their last life, completes or quits the level, especially in platform games. Most modern games, however, save the game to memory at these points, known as auto-saving. Checkpoints might be visible or invisible to the player. Visible checkpoints might give a player a sense of security when activated, but in turn sacrifice some immersion, as checkpoints are intrinsically "gamey" and might even need an explanation of how they work. Invisible checkpoints do not break immersion but make players unsure of where they will respawn. Usually, if a player does get a game over, then their progress will be lost, and the player would lose all of