From: Daniel Aleksandersen [mailto:aleksandersen+ietf(_at_)runbox(_dot_)com]
"Uniform Resource Identifier schemas describe resources. Why
then are some of the themost popular URIs schemas named as actions?
mailto: is an action, whilst email: is a resource. The first
is the standard and widely supported, and the second is not
the standard and is not supported by a single application.
tel: is a resource, whilst callto: is an action. The second
is supported by Skype (a popular calling software) but is not
a standard, and the first is the standard but not supported
by a single application.
The reason is historical, nothing more.
The tag mailto was used to differentiate a mail message from the action of
sending a mail. At the time we had a somewhat functional view of the web and
uris. Mailto was actually implemented by running a script via termcap.
There is something of a case that can be made for differentiating the mode of
communiction: mailto, jabberto etc. Mailto can take a subject argument for
instance. But its not a case I would argue for myself. The parameters are much
better handled in other ways. The mailto URI should be regarded as a
generalized contact identifier for a person or a group of people.
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