With the help of the Internet, information is available almost about anything you can want and everything you need. Doing research can save you time and money on a variety of things. For example, you can learn the most effective and efficient way to cool your home using an air conditioning calculator. This type of online calculator can help you determine how many BTUs you need to cool your dwelling. The term BTU stands for British Thermal Unit and is a unit of energy. BTUs are used in North America and the United Kingdom.