How to get Folder name, File name and other parameters from URL

[eluser]Blue Sapphire[/eluser]
Hi!
How can I get folder name, file name etc from following url:

http://localhost/rq/index.php/ad/dashboard

'ad' : is folder
'dashboard' : is file

Is there any built in function/code in 'CI' for getting above mention thing?

Thanks in advance