The first organic compound is Carbohydrates. Most organisms use is as a primary fuel or their main energy source. They make up cell structures, and they're also used as stored energy in plants. Second is Lipids. If we have any other energy left over in our bodies, we typically will store that as lipids, which a lot of people think of as fats. It also makes up the cell membrane, and coats the leaves of plants to make them waterproof and also protect them from the elements. Third type are proteins. One use of proteins are chemical messengers or hormones. Proteins are useful for receptors and transport channels in order to help things move in and out of the cell. They also help to control and regulate chemical reactions. Another use is for cell structures, like your hair. the last one is for immunity. The fourth and last is Nucleic Acids. There are two main uses in organisms for nucleic acids. The first one is for protein synthesis. The other use is for our hereditary information or how we pass our traits to our offspring.