ROM hacking is the act of modifying the code of a video game ROM file, usually to make changes to the gameplay, graphics, or story. SNES ROM hacks have been around for decades, and some of the most popular and well-regarded hacks include Super Mario World ROM hacks, The Legend of Zelda: A Link to the Past hacks, and Final Fantasy VI hacks.
There are many reasons why people create and play SNES ROM hacks. Some hackers want to improve upon the original game by fixing bugs, adding new features, or making the game more challenging. Others want to create entirely new games by using the assets and code from an existing game. And still others simply want to experiment with the possibilities of ROM hacking.