Computer hackers 180 Computer security 146 Security measures 71 Computer networks 61 Computer crimes 33 Testing 16 Internet 14 Cyberterrorism 13 Examinations 10 Prevention 9 Certification 8 Electronic data processing personnel 8 Penetration testing (Computer security) 7 History 6 Telecommunication 6 Wiretapping 6 Access control 5 Business enterprises 5 Computer software 5 Interviews 4 Moral and ethical aspects 4 Psychology 4 Short stories, American 4 Social aspects 4 Conspiracies 3 Firewalls (Computer security) 3 Investigation 3 Amateurs, manuals 2 Amateurs, manuals 2 Computer graphics 2