When surfing Internet you probably take your anonymity for granted, most of us do. Tapping phones, listening to confidential conversations, reading others' e-mail messages seems like something that only happens in spy movies to "other" people.
However, you probably don't realize just how much information about yourself has potential to get transmitted across Internet every time you go online.
Every computer connected to Internet has "ports" that allow it to connect. A "port" doesn't mean you have a physical hole or opening in your computer's case or hardware, but it does mean you have openings through which information passes back and forth between your computer and Internet.
Depending on type of connection (dial up, LAN, cable, DSL), you may have several openings for potential mischief by hackers, malicious code or viruses.
Computers with dedicated connections rate most at risk. If someone or something gets into one of these ports and into your computer, they can potentially watch everything you do and see all data you enter, including social security numbers and credit card information.
The easiest way to defeat this problem involves using a firewall. Firewalls, simple and inexpensive software available at virtually any office supply or computer store, block most common ports hackers use to enter your computer.
Firewalls also help you detect and block unauthorized transmission of information from your computer to Internet. This adds a significant measure of protection if you get infected with a Trojan Horse virus that tries to "phone home" to hacker with your sensitive information.