Code:
[...URL="http://www.test.com"]try this link[/URL]
turns into

try this link


(although the "code" tags in bbcode are supposed to allow code being shown, I had to insert a ... after the first square bracket!!)

you can key in the code or type "try this link", highlight it, and hit the globe/chain icon and paste your URL in the popup as mr. silver sez.