Congress established the U.S. Army Signal Corps on March 3, 1863, and today it is in charge of communications and information systems support for the armed forces. However, the Signal Corps had other responsibilities, such as army aviation (until May 1918) and photography.
The Photographic Section of the Signal Corps was established in June 1917, and it was responsible for the U.S. Army’s official ground and aerial photography of both World Wars.
A little-known history of the US Army Signal Corps is that of the 18 million photographs in the National Archives, the US Army Sign Corps' collection is the oldest and largest.
Its 1945 images may be the most telling of the war and can be accessed via the following link.
Photo Credit: United States Army Signal Corps