port 80 - technical definition

(1) The default IP port number used by Web servers for Web (HTTP) transactions. Secure HTTP (SHTTP) transactions are handled by port 443. Requests that come into the server at port 80 often result in returning an HTML page to the browser. Port 80 requests may also call a CGI script, ISAPI or ASP process, a server-side include (SSI) or a Java servlet, all of which perform some process in the server and then typically return an HTML page with the results. A request coming into port 80 may result in any file being copied from the Web server to the requesting client.

For the complete list of well-known ports and registered ports used on the Internet, visit www.iana.org/assignments/port-numbers. See TCP/IP port.

(2) An input/output address in a PC used for sending POST codes. See POST and PC I/O addressing.