What is the“Top Five Cards” rule and how does it apply to splitting pots?

Question

I had a problem figuring out the split pot rule the other night, this is the scenario:

I had: 10, 3 My Buddy Had: 10, 5 The Table: K, Q, J, 8, 7

Should the pot be split because we both had the same best five cards? (K, Q, J, 10, 8)

Or did my buddy win because he had a higher kicker?