Information warfare is a large organised effort to obtain and destroy information by whatever means possible with the intent of destroying or taking over a goverment or corporate entity. This guide provides information on the emerging super-intelligent anti-social subculture of hackers and cyber-terrorists as well as practical recommendation on how they can be stopped. The defensive strategies and counter measures are desigined to help companies survive infrastructure attacks, military conflicts, competitive intellegence gathering, economic warfare and corporate espionage. This study answers the need of IT professionals to protect their computer and computer-based assets.