In the United States Navy airman is a rating (job title) indicating a sailor who deals with naval aircraft either on an aircraft carrier or ashore. The insignia for an airman is the same as that of a seaman apprentice or seaman -- diagonal stripes sloping up to the right -- except the stripes are green instead of white.
In the United States Air Force an airman is an enlisted rank just above airman basic and below airman first class. The insignia for an airman is one white downward-facing chevron coming off of a blue circle with a white star in the center. They are addressed as "airman" regardless of gender. The pay grade for this rank is E2 (heh) and it is abbreviated Amn.
An airman continues as an apprentice in their career field but is expected to conform to Air Force regulations.
Going by NATO rank codes, an airman is an OR2 comparable with a Leading Aircraft(wo)man, a Senior Aircraft(wo)man, or a Junior Technician in the Royal Air Force.
Airman is also the general term for any member of the Air Force, Air Force Reserve, or Air National Guard, and is the name of the Air Force's official magazine.
Airman Basic ← United States Military Ranks → Airman First Class
General John F. Curry Award
All "achievements" (steps in grade) are named after illustrious individuals from aviation or military history, and sometimes the leadership test will contain questions on that individual. Curry was the first national commander of Civil Air Patrol waaay back when we were still kicking depth charges out to try to knock out U-boats during World War II.
An airman will continue screwing up flight formations during drill and desperately try to remember whether a diamond on the collar means captain or major. They regularly get yelled at for failing to remember their right from their left, but they're starting to get the hang of CAP now.
An airman wears the one stripe insignia (downward-facing chevron with a tri-prop shield in the center) on their right collar and the silver CAP insignia on their left. They are authorized to wear the Curry award ribbon (solid purple with two thin white lines on either side) on their dress uniform.
All Civil Air Patrol cadets can be addressed as "cadet" by a senior member or member of the armed forces, but within the cadet program they are typically called by their grade -- in this case, "airman." Airman is used for either gender (although just once I would like to hear my flight commander call me airwoman). It is abbreviated C/Amn.
To progress to airman first class, a cadet has to pass a test on chapter two of the leadership handbook with a 70% or higher, complete a cadet physical fitness test (CPFT), attend a moral leadership class, and pass a test on a "module" (why they can't call them chapters, I don't know) from the Aerospace Education manual.
Cadet Airman Basic ← Civil Air Patrol Cadet Grades → Cadet Airman First Class
Wikipedia: Airman, Comparative military ranks
Leadership: 2000 and Beyond