This is a very general guide to the various camouflage patterns used over the years by the U.S. Military. There are more in-depth articles online on the patterns, this is meant to be only a brief review.
Over the years, there have been numerous camouflage patterns worn by the U.S. military. Beginning in 1942, the ARMY followed shortly by the USMC issued a one piece camouflage suit. The fabric used had a green camouflage pattern on one side with a brown pattern, known as the "duck hunter" style on the reverse side. Beginning in late 1942, the USMC issued a similar patterned two piece uniform, as the need for removal of the one piece suit for bodily functions was deemed unacceptable. This pattern was also used during the Korean War.
The ERDL pattern, originally developed in 1948, was used in by the Armed Forces from 1967-1969 in Vietnam. This four color pattern later evolved into what is known as the M81 Woodland pattern, introduced in 1981. This pattern is a good, general purpose camouflage for temperate and tropical environments. This pattern is known worldwide and used by other countries with slight variations.
During the Vietnam War, Rangers and Special Forces units adopted the Vietnamese "Tigerstripe" pattern with its distinctive horizontal slashes of black, green, and tan. This style became popular among the troops, but it was not an official government issue uniform.
The 1980's brought out the Desert 6 Color pattern, used by the US Army during desert exercises. This pattern was designed for rocky and mountains terrain, and unfortunately did not perform well in the desert environment. This pattern was nick-named the chocolate-chip pattern because of it black and white flecks, which resembles chocolate chip cookies.The Desert 3 Color was its replacement, a much simpler designed which performed well. This pattern was authorized for use with all the branched of the U.S. Armed Forces. As with the Woodland pattern, there have been several countries that use a variation of these patterns.
Desert 6 Color Desert 3 Color
The pattern know as "Urban Camouflage" is a variation of the Woodland pattern and not an official pattern used by the military. This pattern emerged in 1990, used by SWAT and special forces, as well as becoming a fashion pattern among young people.
The Night Desert Camouflage pattern was used during the First Gulf War. This two color pattern, a dark green grid with irregular dots on a light green background was a complete failure. Test were later conducted with this pattern and the results show that the pattern actually increased the chance of a soldier being seen. To say the least, it was not in service very long.
Night Desert Camo
The year 2000 brought out the MARPAT (short for MARine PATtern) series of camouflage by the USMC. Known as the Desert Digital and Woodland Digital, this series of camouflage was developed by studying hundreds of after market patterns, in which three were selected and then modified and digitized to create the patterns. It is a far more effective camouflage than standard uniform patterns because it mimics the dappled textures and rough boundaries found in natural settings. The Urban Digital pattern was developed as well, but is not authorized for use by the USMC.
Desert Digital Woodland Digital Urban Digital
The latest in patterns used by the U.S. military are the ACU, or Army Combat Uniform, and the MultiCam pattern. The ACU pattern is also known as "ACUPAT or "ARPAT". The pattern is noticeable for its elimination of the color black, which is not commonly found in nature. The MultiCam pattern was developed by Crye Associates in conjunction with U.S. Army Soldier Systems Center. It has become quite popular among military enthusiasts. Some local, state, and federal law enforcement agencies also make use of the pattern.
ACU Pattern MultiCam
As stated earlier, this is a brief run-down on U.S. military patterns. There are numerous other experimental patterns developed and tested, but not officially issued.