This template wraps a span around a given external html link. If one parameter is passed to the template, the link is presented as is:
{{plain|http://imslpforums.org/}} → http://imslpforums.org/
If two parameters are passed, the displayed text for the link follows the second parameter:
{{plain|http://imslpforums.org/|IMSLP Forums}} → IMSLP Forums
Caveats: Not all links will work without some modification: for example URLs with exclamation marks “!” need to have these escaped as “%21”. Also see here
