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The basic function of a port is to move information from one location to another, either on the same computer or between networked machines.
Ports allow computers to communicate over a network.
Computers have many ports which can be used simultaneously and for a variety of different purposes including mass data transfer, emails, and connecting to the web.
Each port has a different ID number which distinguishes its use.
For example a certain range of ports are used for public programs such as HTTP and FTP, whereas other ports are made available for more wide ranging use.
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