What is a Port?

On big ship with round windows that have hinged covers, those are called port holes. You can throw your message in a bottle out that port hole and hope someone gets it! On a computer a port is also a hole, but it's also an interface. On the back of your computer (and the front and sometimes side too) are holes that you plug devices into.

Most everyone has heard the term USB because practically everything is available for USB (mice, keyboards, printers, cameras, and the list goes on!). The port (hole) that you plug a device into allows your computer messages to go out (to a printer or whatever device you have plugged in). It also allows information to come in.

There are other types of ports available: PS2 (for mice and keyboard) and LPT (for printers) are fading fast and being replaced by USB and Firewire. Com ports used for modems have become less important as they are repleced by high-speed communications. You also can have TCP/IP ports. The IP address of the device you want to connect to becomes the gateway or interface to the device.

So why do you need to know about ports anyways????

1. One reason you need to know about ports is security software. Often they block common things that you need to do such as attach to a printer. Sometimes you have to allow exceptions to your security software so that a port will be allowed which is adding  a hole through which information can travel. These exceptions are defined by you so they are relatively safe.
2. Outlook users need to be aware of ports because Outlook sends email through different port numbers. Because of spamming many internet providers are blocking port 25 (Outlook's default sending port). If you have a problem sending out emails through Outlook at home, then you may need to ask your provider if they block port 25. Mine is Verizon and they do block port 25.

I hope this was a simple enough explanation of ports. If you know what a port is you can get your messages through!