What is a firewall and why should everyone have one on their computer?

What's a firewall? It's a small program that stands guard between your PC and the big, bad world. It keeps you, your PC, and its information safe from all the bad guys out there by not letting them sneak in your PC's backdoor when you're not looking. Would you leave your house without locking the doors? Without a firewall, that's what you're doing to your PC.

A firewall protects your computer from unwanted Internet traffic. The primary function of a firewall is to let good traffic pass through while bad traffic is blocked. The most important part of a firewall is the control features that distinguish between the good and bad traffic.

You need to protect yourself from others having access to your computer while you are on the internet. For many people, this is all the time your computer is on because of high speed internet.

You want to protect all the files and programs that you have on your computer. Without a firewall, anyone who knows how to hack into your computer can do so and many times you won'tt know they have done damage until it's too late. Imagine if all your files disappearing or were changed by a hacker who got onto your computer. It has happened to some people and we read of thishappening all the time!

Your firewall will let you request web pages, download files, chat, etc., while blocking other people on the internet to access your computer. Some firewalls are software that run on your computer and other's are firewalls are hardware like routers.

If your running a network at home, a firewall is a must. If you are still using a "dialup" to connect to the Internet, you need to be somewhat concerned about having a firewall, but not as much as those using cable-modem or DSL connections. It's the folks with the, "always-on," cable and DSL connections that are at greatest risk.

So how do hackers get into your system?
Back when dial-up was your only option dial to the Internet (no offense to those still on dialup), you didn't really have to worry about hackers because every time you dialed into your provider, they would give you a new IP number. Your IP number is how most hackers find your computer. Today with DSL and Cable, you may have a static IP number that never changes or if you have a dynamic one, that number may not change for months at a time. This gives hackers a chance to come back to your IP number if something looks interesting to them. Even if you are on a dial-up connection, you are still vulnerable to hackers.

Hackers don't sit there and manually try every IP number in the world. Tthey have software programs that will do that for them. Once they find an interesting IP number, they can then scan through all your port numbers to see which ones are available for attack. This is also done by software.

A firewall is a must. Some people use software firewall programs and other people use hardware routers. Some recommendation today is to use both. A hardware router will put distance between your computer and the Internet and also afford protection. Then each computer on your network should be running a software firewall. This will offer maximal protection from all the elements.

There are some very good firewalls available for home users. They are easy to install, will configure themselves to your PC, and are fairly inexpensive. Some are even free. If you would like to consider adding this type of software to your PC, here are some firewalls and their Web sites for you to check out and see what you might like to try.

• Zonealert from www.zonelabs.com This is an excellent firewall and it's FREE. Just download and install it. (I use this one at home and I am on a dial-up. It's very easy to configure and use.)

• BlackIce Defender from www.netice.com. This is not a freebie but the cost is minimal (less than $40.

• Norton Personal Firewall from www.symantec.com. You can also test your computer to see how "safe" you are by clicking on the Security Check link. You can also check your exposure to viruses. It will take a few minutes to check your system but it's safe!

• Mcafee Personal Firewall Plus from www.mcafee.com This is a subscription firewall. $34.95 buys you a year of use.