Computer security is the equivalent of playing cops and robbers with a computer. On one side are the bad guys, trying to destroy, modify, or steal data. On the other side are the good guys, trying to protect that data.
In the early days of computers, the biggest threat to data was losing it through an accident. Then malicious computer hackers emerged. Unlike the original band of computer hackers, responsible for creating operating systems and language compilers, malicious hackers use their programming skills to break into computers and hurt others.
Initially these computer break-ins were more of a nuisance than a danger. Computer hackers might tie up resources, but they rarely wrecked anything except by sheer accident. In fact, many computer administrators grudgingly allowed hackers to stay on their computers as long as they didn't disturb anything, and many hackers returned the favor by warning computer system administrators of flaws in their programs that could allow less honorable hackers to sneak in and destroy files.
As more people picked up hacking skills, inevitably a small percentage of these hackers began using their skills for destructive purposes. At first, there was only the joy of crashing a computer or wrecking data for bragging rights to other hackers, but hackers soon had a new motive for breaking into computers. As more people began shopping online and more computers began storing credit card numbers and other personal information, ...