Hip Score

How does Hip Scoring actually work? I've never really looked into this before, I've tried Googling it but haven't found a lot of useful information, most of it is very confusing.

A GSD I know (not the one I'm possibly adopting) has a hip score of 5:6. Is this a particularly good or bad score? Why? What do the two numbers relate to?

Thanks.

Here is some information on Hip dysplasia and hip grades, not specifically the rating that you are looking for.

http://www.offa.org/hipgrade.html

Thanks,
mrbluekittie

those scores would be PennHip.
i might be wrong but i think PennHip scores differe with each breed...and i dont know exactly how the scoring for PennHip works...you'd have to look it up