Nothing in life is completely secure. Think about it - when Julius Caesar took that famous walk to work on a fateful March morning, I'm sure he felt rather secure; after all, he was Caesar. Did Caesar think his life was about to end and become the prototype for countless Mafia hits in Hollywood movies and the real world? Of course not. The Internet and all of its technologies are no exception. Thousands of specific security problems have been discovered and fixed since the inception of the Internet. If you're using up-to-date firewalls, application servers, operating systems, and Web browsers - with all of the latest updates and security patches applied as each vendor prescribes - you are usually safe from known attacks. However, nobody is safe from attacks directed at weaknesses that haven't yet been discovered.

If somebody tells you that anything involving technology is 100% safe because hackers aren't smart enough to exploit vulnerabilities, you're either speaking with a liar or a fool. I've discovered some security problems on my own, and I'm pretty sure that I'm not the smartest person in the world. When one group of hackers creates an attack and shares it with other idiots, we're all in trouble.

There are two classes of security problems: nuisances and security breaches. A nuisance attack merely prevents you from getting your work done; for example, it may cause your computer to crash, delete your files, or give you and all of your associates a virus. In most cases nuisance attacks are initiated by the socially maladjusted, the same people you tend to avoid in the real world. These people are angry over being isolated and they blame society as a whole for their personal disappointments and failures. Learning to write computer code that inconveniences people with real lives really appeals to this group.

Security breaches are more serious. There are two types of security breaches. In the first, your private data is stolen and used by the thieves for some type of financial benefit to themselves. The second type is caused by some type of organized group or government that wants to disrupt the economy. The first group - the world's computer-literate criminal class - puts a tremendous amount of time into trying to steal credit card numbers and other data that can be sold on the open market. These are small groups and individuals with limited resources looking for big payoffs. They are primarily the problem of banks, credits card processors, and large corporate data repositories. The thieves who recently breached a security system to get access to about 5.6 million Visa and MasterCard accounts are of this type.

Visa and MasterCard said the thieves could access as many as 2.2 million accounts after breaching the security system of a company that processes credit card transactions on behalf of merchants. The affected accounts make up almost 1 percent of the 574 million Visa and MasterCard accounts in the United States - now that could be a big payoff.

The other type of breach - the kind aimed at disrupting our economy - is everyone's problem. The groups behind such attacks have potentially unlimited budgets to do whatever damage they may want to inflict. We are standing on the verge of the world's first virtual war - a war that will have real-world consequences. Currently there is no easy way to protect yourself from this last group, as they are playing by the real rules of war.

The one thing you should never do is to glorify these groups by calling them hackers, as they wear the name like a badge of honor. Call them what they really are - idiots, fools, thieves, and criminals. As long as there is some perceived benefit to people who cause computer trouble - be it for fun, profit, or political goals - security will remain an issue.

To quote Don Corleone, "This is the business that we have chosen to be in."