Wall hacking

Wall Hacking is when players use glitches in the Halo physics engine that allows players and objects to go through walls and barriers, usually to cheat. One common and well-known example of this is on the Multiplayer map Danger Canyon on Halo: Combat Evolved. Because this map is arranged in a circle, with the two bases next to each other (albeit with a wall in between), if you flew through the wall, you would get to the opposing team's base. People have done this in Team CTF games when Team Kill / Friendly Fire is turned off in the game settings, 'ramming' another teammate through the wall with a high-speed land vehicle like a Ghost or a Warthog, and the 'rammed' player breaking through the walls to the other side. If the process didn't go fast enough, they might fall between the two walls and die from fall damage.