As the sixth century B.C. Chinese military strategist and  philosopher Sun Tzu stated in his famous military text The Art of War:  “If you know the enemy and know yourself you need not fear the results  of a hundred battles.” Once you understand how hackers think, the tools  they use, their exploits, and their attack techniques, you can then  create effective defenses to protect against them. Understanding hacking  not only improves network security; it also maintains security at a  high level of readiness.     Why is understanding hacking, exploitation, vulnerabilities,  and attacks critically important? What motivates hackers to attack  computer networks? Why does anyone get involved in illicit activity  outside the mainstream?