Calories seem to be this ominous, intangible concept. Sometimes things we think should be low on calories are surprisingly high, and vice versa. So what are calories exactly? Well, you could look up a scientific definition. But after you've awaken from your boredom-induced slumber, try feasting your eyes (pun intended) on these 200 calorie photos by WiseGeek. Whether a plate of bacon, gummy bears, celery, or apples, 200 calories comes in a wide variety of foods. See even more images here.