He doesn't wear a mask on his face and he doesn't break a window to get into your house. He doesn't put a gun to your head or trash your personal belongings. He's still a thief. Although this thief is a thief you will never see, but you may not even realize right away that he stole from you. The thief is a hacker and he "enters" your home through your computer, accessing personal information, such as credit card numbers, which he could then use without your knowledge at least until you get your next credit card statement. RichardBernes, supervisor of the FBI's Hi-Tech Team in San Jose, California, calls the Internet "the open window of cyberspace through which thieves crawl" (Erickson 1). There appears to be unlimited potential for the theft of credit card numbers, bank statements, and other financial and personal information transmitted over the Internet. It's hard to imagine that anyone in today's technological world can function without a computer. Personal computers are linked to business computers and financial networks, and all are linked together via the Internet or other networks. More than one hundred million electronic messages pass through cyberspace every day, and every piece of information stored on a computer is vulnerable to attack (Icove-Seger-VonStorch 1). Yesterday's bank robbers have become today's computer hackers. They can escape a computer crime with millions of virtual dollars (in the form of information they can use or sell for a huge profit). Walking away is precisely what they do. The National Computer Crimes Squad estimates that 85 to 97 percent of the time, information theft from computers goes undetected (Icove-Seger-VonStorch 1). Personal computer users are vulnerable not only to credit card information and login credentials, but also to their files, disks, and other computer equipment and data, which are subject to attack. Even if this information is not confidential, having to reconstruct what was destroyed by a hacker can take days (Icove-Seger-VonStorch 1). William Cheswick, a network security specialist at AT&T Bell Labs, says personal computers that use the Internet are particularly vulnerable to attacks. “The Internet is like a safe with a screen door in the back,” says Cheswick. “I don’t need jackhammers and atomic bombs to get in when I can get through the door” (Quittner 44). Using the Internet has become one of the most popular means of communication.