Youtuber Summoning Salt released a fascinating video about the history speedrunning the original Super Mario Bros game for the Nintendo Entertainment System. The video chronicles how many people combined over the course of several decades came together to create the most efficient path for the speed run of the game. It's an interesting part of gaming history that not a lot of people know about. 

In short the video is about the level 4-2 one of the most famous in game, and how by using a couple of very complicated tricks speed runners were able to trick the game into thinking that Mario was several frames ahead of where he was supposed to be. Normally in the game Mario is 112 pixels across the screen but by bumping into different objects in a certain way it could propel players farther along the level. The reason this is important is because back when the game was developed it only allowed one warp zone to be loaded into the game at once, and 4-2 was unique because it had a section of the level with 2 different warp zones back to back. By manipulating the position of Mario in the level players could essentially glitch themselves into the fast warp zone by using these methods.

It's a really interesting video. Whether you are into speed running or not I would give it a watch. It's crazy how only a couple frames of animation can make all the difference in a world record speed run.