Your best defense against hackers may be knowledge plus some software

Control Panel Usersguide  

A term you hear often is “firewalls.” But what is a firewall? A firewall is a wall between two rooms or spaces which prevents, or hopes to prevent, fire from spreading from one room to another. So if one room catches on fire the fire will not be able to breach or break through the firewall to reach and damage the other room. Firewalls are not absolute barriers but serve to prevent most openings or slow the fire’s damage. A firewall on the internet is similar—it serves to prevent one computer from compromising another computer.

There are two types of firewalls used currently: software and hardware. A software firewall is a computer program running on a computer which performs it’s duties on that computer. We will discuss its duties in a moment but now realize that a software firewall is just bits of code on a computer. A hardeware firewall is a physical piece of equipment designed to perform firewall duties. A hardware firewall may actually be another computer or a dedicated piece of equipment with its only function being serving as a firewall.

So what does a internet firewall do? The reality of the situation is that it keeps out malicious hackers and people who seek to do damage and/or take over other peoples’ servers. Firewalls really serve no other purpose. Firewalls seek to limit the access to a server or computer and let in only the people who need to be there. Firewalls also attempt to limit the impact of computer viruses from spreading and preventing individuals from running a DOS attack. (A DOS attack is a Denial of Service attack which attempts to stop the server from responding or running on the internet by flooding it with millions of attacks.)

By having a good firewall you eliminate some risks with a computer on the internet and hopefully keep out the malicious people. Will a firewall guarantee that a server will not be compromised? No, but like a real firewall, it does slow the fire, or in this case the attacks, so they can be dealt with before the real damage is done. Firewalls constantly have to be tweaked or fine-tuned to keep out the latest tricks and traps set by the hackers.