Action Replay is the brand name of a series of video-game cheating devices (such as cheat cartridges) created by Datel. 

Typically options include cheats, level warping, and display of internal game data not normally viewable by the player.

• Infinite lives, invulnerability, permanent power-ups, no collision detection, walk through walls, one-hit kills, super-high jumps, infinite money, etc.
• Obtain any item in the game, even those not normally obtainable (e.g. debug or removed items).
• Access or warp to any level, even those not normally accessible (e.g. test or unused levels).
• Activate debug menus, normally used by programmers when testing and debugging a game.
• Download, upload, import and export save games to the Internet or a storage device.
• Save game state to disk, so it can be restarted from that point even if the game does not support saving.
• Region-free operation.
• Loading of third-party homebrew applications/games, not backup copies of retail games.

Information About Datel: