1. A computerphile; a person who is totally engrossed in computer technology and computer programming or who likes to examine the code of operating systems and other programs to see how they work.
2. A person, more commonly considered a cracker, who uses computer expertise for illicit ends, such as by gaining access to computer systems without permission and tampering with programs and data. Also called: cracker. See also hacktivist.
3. A programmer for whom computing is its own reward; may enjoy the challenge of breaking into other computers. Someone who engages in the activity of hacking computer programs, systems, or networks.