Weapon Camouflage

Weapon Camouflage, usually referred to as Camo, is a colored pattern applied to weapons to allow them to blend in to environments, although it is more often used for players to "show off" their achievements in-game as in Call of Duty 4: Modern Warfare and Call of Duty: Modern Warfare 2 camouflages are unlocked by Headshots. In Call of Duty: Black Ops, camouflages can be purchased for each, with the exception of Golden Camouflage, which costs  and is available only after the player has Prestiged 14 times. In Call of Duty: Modern Warfare 3, weapon camouflage is achieved by increasing the weapon level of a weapon.

Camouflages can be applied to primary weapons in Call of Duty 4: Modern Warfare, Call of Duty: Modern Warfare 2, Call of Duty: Black Ops, and Call of Duty: Modern Warfare 3.

Camouflages were planned to be in Call of Duty: World at War, but Treyarch canceled this idea to save memory. In addition (according to them), camouflage on most weapons did not look appealing.

Call of Duty 4: Modern Warfare

 * Alternate Desert Camouflage - A camouflage found on the M21 in The Bog using the "Give All" command.
 * Desert Camouflage - A camouflage based on brown and beige colors. Available immediately.
 * Woodland Camouflage - A camouflage based on brown and green colors. Available immediately. (Note: During the campaign mission "One Shot, One Kill" a unique, predominantly green and black woodland camouflage is present on both the player's and Captain MacMillan's M21 rifles.
 * Ghillie Suit Camouflage - During the campaign mission All Ghillied Up, both the player's and Captain MacMillan's M21 rifles are covered in a camouflage wrap similar to their ghillie suits.
 * Digital Camouflage - A camouflage based on gray and black colors. Unlocked at 25 headshots.
 * Blue Tiger Camouflage - A camouflage based on blue and black colors. Unlocked at 75 headshots (50 for shotguns).
 * Red Tiger Camouflage - A camouflage based on red and black colors. It appears as mere red lines along the gun's normal furniture. Unlocked at 150 headshots (100 for shotguns).
 * Golden Camouflage - A golden camouflage. Complete all challenges for that category of weapon (for example, a golden AK-47 requires all of the assault rifles' challenges complete). Once all challenges are completed for a category of weapon, players will unlock a gold covered variant of one particular weapon from that category. Players can only unlock gold camouflage versions of the AK-47, Mini Uzi, M1014, M60E4 and Dragunov in this manner. Golden Camouflage is also unlocked automatically for the Desert Eagle at Level 55.

Call of Duty: World at War

 * Reich
 * Siberian
 * Royal
 * Yankee
 * Rising Sun
 * Golden Camouflage
 * Blood
 * Olive
 * Setting Sun
 * Jewel
 * Ocean

Call of Duty: Modern Warfare 2

 * Unknown Arctic Camouflage - A variant featured on the player's ACR rifle during the campaign mission "Cliffhanger". It features several blue hues, most closely resembling a hybrid between the Arctic camouflage, and the Warsaw camouflage from Call of Duty: Black Ops.
 * White Tape Camouflage - A camouflage made out of white tape, found only on the FAMAS, and only in campaign and Spec Ops.
 * Desert Camouflage - A camouflage based on brown and beige colors. Available immediately.
 * Arctic Camouflage - A camouflage based on white and gray colors. Available immediately. Also, in campaign, a SPAS-12 can be found that has a white handguard, functioning as basic arctic camouflage.
 * Woodland Camouflage - A camouflage based on brown and green colors. Unlocked at 5 headshots.
 * Digital Camouflage - A camouflage based on black and gray colors. Unlocked at 15 headshots.
 * Urban Camouflage - A camouflage based on red, white, gray and black colors. Unlocked at 30 headshots.
 * Blue Tiger Camouflage - A camouflage based on blue and black colors. Unlocked at 75 headshots.
 * Red Tiger Camouflage - A camouflage based on red and black colors. Unlocked at 150 headshots.
 * Fall Camouflage - A camouflage based on brown, orange, yellow, and black colors (when applied to some weapons, however, it also gains purple). Unlocked at 250 headshots.

Call of Duty: Black Ops
All camouflages are unlocked at level 22 and available for purchase with the exception of Golden Camouflage, which is unlocked once the player reaches Prestige 14.
 * Dusty Camouflage - Flat, tan finish.
 * Ice Camouflage - Flat, sky blue finish.
 * Red Camouflage - Flat, red finish.
 * Olive Camouflage - Flat, olive finish.
 * Nevada Camouflage - Similar to Desert camouflage, but less mottled.
 * Sahara Camouflage - Mix of Desert and Fall camouflage.
 * ERDL Camouflage - Camouflage consisting of green, gray, and light and dark browns.
 * Tiger Camouflage - Colors of a tiger, with boldly-contrasting Orange and Black.
 * Berlin Camouflage - Similar to Urban, but with olive instead of gray.
 * Warsaw Camouflage - Similar to Urban camouflage, but with a green/turquoise color instead of red.
 * Siberia Camouflage- White with almost sparkly, good contrasting blue square-like shapes.
 * Yukon Camouflage - White, gray, and black.
 * Woodland Camouflage - Different greens and some browns, just like a forest.
 * Flora Camouflage - Green colors and brown, darker than Woodland camouflage.
 * Golden Camouflage - Pure Gold, Unlocked at prestige 14 for 50,000.

Call of Duty: Modern Warfare 3
Weapon camouflages return again in Call of Duty: Modern Warfare 3. Camouflages are earned by ranking up one's weapon rather than through headshot challenges. There are no secondary weapon camouflages present in the game.

There are thirteen weapon camouflages:
 * Classic
 * Snow
 * Multicam
 * Digital Urban
 * Hex
 * Choco
 * Snake
 * Blue
 * Red
 * Autumn
 * Gold
 * Winter (Call of Duty ELITE founders only)
 * Marine (Wii only, also applicable via modding for other platforms)

Trivia

 * In Call of Duty 4: Modern Warfare and Call of Duty: World at War game files there are references to the Prestige camouflage. The description says "Go get some sun", and codename for unlock condition is "PERKS_ALL_PLAY_AND_NO_WORK".
 * In Call of Duty: Modern Warfare 2, it is possible to apply camouflage to PP2000, TMP, SPAS-12, AA-12, Striker and M1014 via modding the game files, suggesting camouflages were planned to be featured on secondary weapons. There were also camouflages seen on secondary weapons in ''Call of Duty: Modern Warfare 3 trailers prior to release, but were cut out for unknown reason.
 * On the Wii version of Call of Duty: Black Ops, weapon camouflages only appear on the first person model of the weapon, and the third person model will have the default skin. This is due to the Wii's graphical limitations.
 * In early Call of Duty: Modern Warfare 2 development stages, the Call Of Duty 4: Modern Warfare woodland camouflage was used instead of the current one. This can be found within the game files as the "bushdweller" camouflage.
 * For the PC version of Call of Duty: Modern Warfare 2, it is possible to install custom camouflages.
 * In Call of Duty: Modern Warfare 3, if the player has founders status on Call of Duty ELITE, the player will unlock the Winter Camouflage, which is located at the bottom of the camos list.
 * In Call of Duty: Modern Warfare 3, camouflage no longer covers optical attachments or heartbeat sensors.