ROM hacking

ROM hacking is the process of changing a ROM image or ROM file to change the contents contained within, usually of a video game to change the game's graphics, story, levels, gameplay, and other elements. This is usually done by technically inclined video game fans to make a old game better, as a creative outlet, or to make new content, unofficial games using the old game's engine.

ROM hacking is generally done by use of a hex editor (a program for editing data) and other tools such as tile editors, and game-specific tools which are generally used for editing levels, items, and the like, by using more advanced tools such as assemblers and debuggers are sometimes used. Once done, they are usually posted on the Internet for others to play on an emulator or a games console.