Cap and share is a plan that helps to limit how much pollution there is. It works by setting a "cap" on the amount of pollution that companies can make. This means that each company will only be able to make a certain amount of pollution and no more. Then the government or other organizations will "share" the money from the companies that made more pollution than their cap. The money that is shared can be used to help pay for renewable energy, like solar or wind power, or other things that help to make the environment more clean and healthy.