A software firewall should be enabled and or installed onto each computer regardless whether your have a hardware firewall or not. It is best to use both hardware firewall and a software firewall.
It is very straightforward to install the software firewall using your operating system's normal installation procedure, i.e. run the installer program which will be described in the firewall documentation.
You may want to consider a third party software firewall as opposed to the ones provided by the operating system vendor due to the lack of certain features, especially the egress feature (as discussed in the section above).
Never use two or more firewalls at the same time. Always completely un-install one before installing another firewall.
If you are not sure of which software firewall to choose for your operating system - have a look at the following offerings from the various manufacturers (not listed in any particular order):
Microsoft Windows:
-
Zonealarm personal firewall
-
Norton Firewall (Symantec)
-
Kerio
-
Kaspersky (as part of the Internet Security suite).
-
McAfee Personal Firewall
-
BlackICE
-
F-Secure
The following are examples of the types of software (or personal) firewalls for the PC.
Apple Mac OS:
-
Norton Personal Firewall for Macintosh (Symantec)
-
Netbarrier X3 (Intego)
-
Brick House
The following are examples of the types of software (or personal) firewalls for the Mac.
Note: A lot of the manufacturers produce “free for personal use” versions of their core products i.e. software firewalls. Thus before spending money with them check if there is a “free for personal use” version of their product and if its basic functionally is sufficient for your requirements. Normally if you are starting out then the basic free for personal use version is more than adequate.
delicious [1] | 
digg [2] | 
reddit [3] | 
furl [4] | 
yahoo [5]