Encore: remote access Trojan or RAT (noun)
From the intrusion kill chain model, a program that provides command and control services for an attack campaign. While the first ever deployed RAT is unknown, one early example is Back Orifice made famous by the notorious hacktivist group called “The Cult of the Dead Cow,” or cDc, Back Orifice was written by the hacker, Sir Dystic AKA Josh Bookbinder and released to the public at DEFCON in 1998.