URL's

The World Wide Web uses Uniform Resource Locators (URL's) to specify the location of files on other servers. A URL includes the type of resource being accessed (e.g., Web, gopher, FTP) , the address of the server, and the location of the file.

The syntax is:

scheme://host.domain (:port)/path/filename

where scheme is one of;

File
    a file on a local system
FTP
    ;a file on a anonymous FTP server
HTTP
    a file on a World Wide Web Server
Gopher
    a file on a Gopher server
WAIS
    a file on a WAIS server
NEWS
    a Usenet newsgroup
TELNET
    a connection to a Telnet-based service

The port number can generally be omitted. Unless someone tells you otherwise, leave it out.