Non-Stadia: Those athletic events that are held outside of the stadium usually on road and/or cross country courses. They are usually the longer distance events.
Stadia: Those athletic events that are generally held within the Stadium usually running events on an oval track, and jumping and throwing events held on various specialized fields.
Masters: Women and Men of age 35 and up.
WMA: World Masters Athletics, the World Association of Masters Athletes. The organization designated by the IAAF to conduct the worldwide sport of Masters (Veterans) and Athletics (Track and Field).