Butter is made by skimming the cream off of unhomogenized milk, then churning it until it solidifies into fat that is solid at room temperature. There is some processing involved in making butter, in the most basic sense of that term, though the processing doesn't have to involve cooking. That said, if you bought butter from a store in the United States, most likely it will have been made from milk that was pasturized, so its fats will have been altered and some of its polyunsaturated fats (omega 6 and omega 3 fatty acids) will have oxidized a little. Although raw butter made from raw (unpasturized) milk from 100% grass fed cows is tasty, it's terribly hard to find and when you can find it it's often very expensive. I just buy raw back fat or suet from beef cattle, or from goats or sheep. It's completely unprocessed and so much cheaper, often less than $3 per pound.