Every web server runs data packets through a pre-designated “port” which is associated with a computer’s network driver. By default, websites most commonly use port 80 and are not seen when browsing to a website. However, a web port can be accessed by typing : and a number.
So, if you run a web server on your computer, you can tell it to run at localhost:8080, where 8080 is the port and localhost is the friendly name for a computer’s “home” address. Ports are useful for setting up fast data streams, running multiple web servers simultaneously, or for using network protocols for software other than a web browser, such as Skype.