One way of find answers is learning how to search. As a simple example, I put "pdd files" into Google and came up with the fact that they are Adobe print driver files.
Perfectfit is a name used by WordPerfect, but there are also other companies using that name.
asf files appear to be audio files because a simple search show methods of converting them to MPEG files.
Raw files are associated with digital cameras and Adobe also makes a converter for them.
And so on and so on.
How about doing a little easy work on your own?? Learning to search is one of the most useful skill for those who wish to frequent this type of Forum.
Regards.