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The TCP/IP Guide  9  TCP/IP Application Layer Protocols, Services and Applications (OSI Layers 5, 6 and 7)       9  TCP/IP Key Applications and Application Protocols            9  TCP/IP Application Layer Addressing: Uniform Resource Identifiers, Locators and Names (URIs, URLs and URNs)                 9  Uniform Resource Locators (URLs)

URL General Syntax 1 2 3 4 5 URL Relative Syntax and Base URLs

URL Syntax for Sending Electronic Mail (mailto)

A special syntax is defined to allow a URL to represent the command to send mail to a user:

mailto:<e-mail-address>

The e-mail address is in standard Internet form: “<username>@<domainname>”. This is really an unusual type of URL because it does not really represent an object at all, though a person can be considered a type of “resource”.

The syntax for the Gopher Protocol is similar to that of HTTP and FTP:

gopher://<host>:<port>/<gopher-path>

See the topic on the Gopher protocol for more information on Gopher paths and how the protocol operates.

URL General Syntax 1 2 3 4 5 URL Relative Syntax and Base URLs