Like its predecessors in the Call of Duty series, Call of Duty: Ghosts comes with a host of camos for you to customize your weapons with. These camos don't do anything besides make your weapon look cool and give your enemies a sense of who you are and what your deal is when you run around killing them with a pink, Hello Kitty-themed camouflage on your big-ass M249 SAW.
Like previous games, you'll have to unlock them before you can use them, but we don't have any information on how to do that at the moment. Presumably, you'll unlock them by playing through the multiplayer portion of the game and acquire them as you accomplish various feats such as killing 10,000 dudes with a specific weapon, or something.
Thanks to a leaker going by the name of @slav_on_my_nob we have images of these camos and all the guns they'll be used on.
Weapons Camos
Snow, Brush, Autumn, Ocean, Scale, Red, Cuastic, Crocodile, Green, Net, Trail, Woodland and Gold.
Assault Rifles
SC-2010, SA0-805, AK-12, FAD, Remington R5, MSBS, Honey Badger, and ARX-160
Submachine Guns
Bizon, CBJ-MS, Vector CRB, Vepr, K7, and MTAR-X
Light Machine Guns
Ameli, M27-IAR, LSAT, Chain SAW
Shotguns
Bulldog, FP6, MTS-255, Tac 12
Sniper Rifles
USR, L1155, Lynx, VKS
Marksman Rifles
IA2, Mk 14 EBR, MR-28, SVU Dragunov