Non-pilot airmen include mechanics, repairmen, parachute riggers, ground instructors, dispatchers, flight navigators and flight engineers. The data only lists those pilots who did not opt to have their information withheld under the Wendell H. Ford Aviation Investment and Reform Act, which took effect in April 2000. As a result, this database is an incomplete listing of the airmen certified in the United States. Names, addresses, dates of medical certification, type of flight certificate and ratings are included in the data. Certificate refers to whether they are a pilot, flight instructors, repairman, etc.
Ratings refer to the type of plane they are certified to fly.
This is the main table, with one record for each airman whose name was released publicly. This includes their address and medical information. This includes one record for each certificate type held, so it's possible there is more than one record for each person. This shows the certificates and ratings. Here are some tipsheets on aviation available from the IRE Resource Center.