Perhaps the most famous of glitches used by speedrunners is the Backwards Long Jump. This glitch belongs to a category of glitches in Super Mario 64 called Hyperspeed Glitches. If Mario long jumps backwards on the right geometry, he will gain incredible speed.

The Backwards Long-Jump glitch: To do this glitch, you have to have the second key to the second Bowser boss. Then, catch some running speed and press the Z button and then immediately press A to do the backwards long jump while reversing the direction held on the joystick.