Regarding Media Player Detection on Client System . please... its.... urgent

Question

hi dear

i wanna know that how can we detect the media player available on client system and then displaying them in a list  and when user select as one of them songs should be played using that media player (which is on server).

also is it necessary that there should be atleast a media player to play songs or we can play songs regardless of the availablility of media player.


please its.... urgent....

regards

vishal