Calories on a food label, exercise bike, or wearable fitness device:
• energy required to raise 1 gram of water 1 degree Celsius
• energy required to raise 1 gram of water 1 kilodegree Farenheight
• energy required to raise 1 kilogram of water 1 degree Celsius
• energy required to raise 1 kilogram of water 1 degree Farenheight