Note that if all you want to do is past in a URL and have it display as a link, you need not wrap it in "URL" tags:
http://capitals.nhl.com (not wrapped in URL tags) produces the same result as
http://capitals.nhl.com (wrapped in URL tags).
The URL tags matter most in the example given by "1" and the second example given by kphoger, both of which substitute text for the URL. (The interesting thing is, if you wrap it in the tags but don't use text, the forum software will revise the tags to be in the format used in their second examples and will simply duplicate the URL twice. You'll see what I mean if you quote this post.)