SFOD-D-1st is short for [S]pecial [F]orces [O]peration [D]etachment [D]elta [1]st or better known as Delta Force. They perform the same operations that of SEAL Team 6 (Black Ops). The only difference is that Delta is a unit under the U.S. Army and the SEALs are under the U.S. Navy but they both are tier one Anti-terrorism Units.