From PortWiki

Welcome to PortWiki

PortWiki is a wiki-style networking resource site. It provides an index of which ports are used in internet applications and games, port forwarding tutorials on how you can configure your router and firewall, guides to creating your own application or game servers and finally a rich database of all 65534 TCP and UDP Ports and their functions.

How Can I Utilize PortWiki?

When you use an internet application or game, a request goes through a specific 'port' depending on it's purpose. For example, HTTP or basic web browsing works through TCP port number 80 while sending emails works through TCP port number 25. Although you may have never heard of this concept before it is happening right as your viewing this site.

To prevent un-authorized traffic from passing from the outside world into your computer, a program or application called a 'Firewall' monitors all 65534 ports detecting any improper use. However, the Firewall does not know every good from bad message being sent and received and therefore can cause problems when using internet application or games - thus, where PortWiki comes in handy. PortWiki will develop to have an index of all the TCP and UDP ports used by certain applications or games meaning network administrators or users can find out which ports they need to 'allow' in order to receive or send the proper information. This is known as Port Forwarding.