Super Mario Bros. Special occupies a strange place in Mario history. It's one of the few Mario games produced for a system other than Nintendo's own, licensed by Hudson Soft for the Japanese PC-8801 computer system. The system was fairly weak compared to an NES, so it didn't scroll; when Mario gets to the edge of the screen, it flips to the next. The game wasn't always designed with that in mind however, leading to a lot of blind jumps. You can play a hacked version of the original Super Mario Bros. designed to recreate this game using the patch found here. And here's a video playthrough of the whole game: World 1, World 2, World 3, World 4, World 5, World 6, World 7, World 8, Last level & ending. And here's a trap room in World 4.