There are different categories of honey(Info from http://www.honeyo.com/types.shtml):
Comb Honey (honeycomb)
Direct from the hive honey-filled beeswax comb as stored naturally by the bees.
Liquid Honey (extracted)
Prepared by cutting off the wax cappings and whirling the comb in a honey extractor, where centrifugal force moves the honey out of the cells.
Creamed Honey (granulated)
Made by blending one part finely granulated honey with nine parts liquid honey. The mixture is stored at about 57 degrees until it becomes firm.
Comb honey in a jar with liquid honey poured around it.
There are many different types of honey, but the best for skin care is Manuka honey. This honey is gathered from Manuka bushes, primarily in New Zealand. I heard somewhere, so I'm not 100% that this is the same bush we get tea tree oil from...but don't quote me on that!! Manuka honey has special anti bacterial powers, which are graded by 'Unique Manuka Factor' (UMF).
10 is the minimum grade it can be to have an affect. Honey which is 10 or above is ACTIVE Manuka honey, but you must be careful, as a lot of honeys are marketed as active, but are not. If you want to learn more, I found this website (http://www.manukahoney.co.uk/index.shtml) extremely helpful.
I love this stuff, I bought a bottle from Marks & Spencers, it was around £10 - Oh yeah, the stuff is not cheap if you want a good quality honey. You can get it online, but be careful you buy good quality stuff which has been approved to have no less than a grade 10. Mine below has a 10+ grading.