What is a Firewall
Since you are reading this article, I would venture a guess that you have gotten connected to the Internet. If you aren’t, please let me know your secrets.
According to a Pew survey post in June of this year, 63% of all American households have broadband connections at home. This means that 2/3rds of all American homes have always on access to the Internet. Now that is great for ease and instant availability of the web, it also means your computer is sitting out there for the world to see and try and get into.
Now, I am not trying to imply that every user of the Internet is trying to hack every other user, but a lot of organized criminal groups, as well as bored intelligent people are trying to get into your computer to get your personal information, user your computer to send spam, infect other people, etc.
Besides a good updated Antivirus utility, what else can I do?
Firewalls.
What are firewalls you are wondering. Think of it as a very sturdy brick wall that blocks all views in and out. That is the most secured you possibly can be. The model for most firewalls is known as deny by rule, allow by exception. What does that mean for you, unless you specifically say I want to allow this service (Email, Web Browsing, FTP, what have you) it will be blocked.
Now firewalls come in two types: Software (Norton Internet Security, Comodo, McAfee Firewall, as well as many others) and “Hardware”. The hardware types are normally found in modern Broadband routers.
Software Firewalls.
Now most windows users, and I can’t speak for Mac or Unix so don’t flame me for that, have a firewall already built in and enabled by default. Do I think you should rely on that? No. There are many add on applications, some I listed above, I think do a better job, but not as easily configured, but they are coming a long way from where they were.
Now the thing to remember about most software firewalls, they are learning firewalls, they will ask you if a new program is attempting to connect to the Internet and prompt you to allow or not. If you did not install a new program or you do not recognize the connection, deny.
I am not going to get into a review right now, but comments and recommendations are welcomed and encouraged. But for my personal use, I have Comodo installed now.
Hardware Firewalls:
For the most part you will not even get into the firewall controls on your router, other then to enable them. You have to know a bit of information to make these modifications. You will want to know which IP address of your local computers, which port and if the port is TCP or UDP. For the average user, it’s not worth the work, but the options are there.
So you have installed and configured your firewall, now what? Well, if you are like me, you will want to run some tests, just to give you the warm fuzzies. I use a few sites and I am sure there are many, many more out there. The sites I use are: Shield’s Up and AuditMyPc.

Not sure that this is true:), but thanks for a post.
I suggest to you to describe the difference between simple Packet-filters Firewalls and Proxy Firewall.
And also between status filter firewalls and status-less.
However, very interesting post! Well done!