Caramelizing is when carbohydrates (especially sugars) are heated and turn brown. Bread is heated in the toaster and, once caramelized, becomes toast. Potatoes are roasted in the oven and develop a crisp brown coating. Onions are sauteed to super sweetness... this is carmelization. But if you take that heat too far, the caramelization crosses the line into burning - which is most definitely not delicious. Taking a food to the point of caramelization - but not beyond - takes attention and some practice. Practicing with sugar, for example, is relatively inexpensive and helps you discern the difference between lovely golden caramel and just plain burnt sugar. The aroma is strong enough that you know immediately! Place a half cup of sugar in a small saucepan over medium high heat and watch the color change. Careful, though, it's hot! When you finally have the knack of it, you'll be able to discern the difference between caramelized and burned - and be able to apply the technique to other delicious foods.