Super Mario World/Main characters
Mario and Luigi are the main characters in Super Mario World, and they are the only playable characters. In single-player games, the player must use Mario. In two-player games, the first player must use Mario, while the second player must use Luigi.
Unlike certain Mario games, such as Super Mario Bros. 2 USA, there are no gameplay differences between the Mario and Luigi. Both characters run at the same speed, jump the same height, and so forth. In the original version of Super Mario World the two are also identical in appearance except that Mario wears a red shirt and Luigi wears a green shirt. However, in the Super Mario All-Stars + Super Mario World version Luigi is slightly taller than Mario, but the two are still identical in terms of gameplay.