Excuse my ignorance, but what the hell is "chams?"
Chameleon skins, cham-hacks or chams, replace player model textures with brightly colored skins, often bright red/yellow or blue/green, that change color depending on whether the model is visible. For instance, an exposed part of an opponent would be shown in a different color, giving a cham-hack user an advantage over non-hack users, especially in games in which camouflage techniques (provided by in-game mechanics, objects or player models) are negated.
While cham-hacks are accomplished using a wallhack subset, historically, user settings (in Quakeworld, for example) or exploits in many older games allowed replacing skins arbitrarily with varying degrees of success?from pseudo-camouflage in dark areas of a map (prior to specular and other advanced lighting techniques) when using a "shadow skin"; to completely disappearing while the skin change propagated to other players; to forcing a plain-white skin on all opponents.
A more obvious skin cheat involves a person wearing a skin that makes him invisible to all players. However, this is a cheat that is easily discovered, especially if the game provides a killcam after each death.
nothing wiki doesnt know.. i knew this but didnt know how to explain lol