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Matthew Francis
Matthew Francis
6,967 Points

What is a port number? (eg; port 80)

What is a port number and what's the importance of a port number? For example, when launching a web, we need to launch port 80. I'm guessing a port number/server/IP address are all interrelated?

1 Answer

Steven Parker
Steven Parker
224,849 Points

Your guess is very good! Just like an IP address identifies a particular machine, a port number identifies a particular connection with that machine. Many port numbers are associated with particular services, and port 80 identifies HTTP traffic for a Web server and is the most common well-known port. The Internet Assigned Numbers Authority (IANA) maintains an official registry of port numbers and associated services.

There's also a Wikipedia page you may find useful.