Fresh Milk/Raw milk is as an oil/water emulsion. It's also known in some circles as a colloidal suspension.
To make every gallon of milk, a cow must pump from 600-800 gallons of blood through her udder. Think of that next time you pour yourself a glass. That cow poured her heart into it!
Whole raw milk's composition varies slightly among cow species, type of food and other conditions, so the figures below (and, at right, from a commercial raw milk dairy) are only approximations.
Here's a rough breakdown in percent of total volume:
Water 87.3%
Milk Fats 3.9%
Non-fat Solids (Protein, Milk Sugar, Immune Factors, etc.) 8.8%