about url links

i want to posts link and shorten them by adding url code
here’s a example:
the name of the file i uploaded is “crimson.rar”
the original link :

in the post i want this link to be appeared like this
crimson.rar
and when clicking it
it will redirect them to that site

in phpbb i had to add a simple url code
like this:
[url=http://www.mediafire.com/f54sa56f2]crimson.rar[/url]
so please help me
and thanks in advance