Special forces or special operations forces are highly trained military units that perform unconventional or unorthodox secret missions concerning a nation’s security interests. There have been many special forces throughout warfare specializing in covert operations rather than conventional combat. Some missions they take on are security performance, movement operations, and counterterrorism missions. Special forces service members are among the military's most mentally and physically formidable fighters. In general, these individuals are late-twenties veterans with families who are intelligent and resourceful. Furthermore, they may have a college degree, have been educated in numerous tactical programs, and enjoy solving problems, such as chess.