Hacker may refer to:
Technology
* Hacker (term), a term used in computing for several types of person
o Hacker (computer security) or cracker, who accesses a computer system by circumventing its security system
o Hacker (hobbyist), who makes innovative customizations or combinations of retail electronic and computer equipment
o Hacker (programmer subculture), who shares an anti-authoritarian approach to software development now associated with the free software movement
*above from wikipedia
I would have to say a crack is a form of a hack according to wikipedia =D Hacking is not any word that is evil, it is media that has twisted the definition to make it seem evil.
If you want to learn more and discuss some great topics in regard to computer hacking and security, check out
http://www.hackforums.net/