Many households are starting to use reverse osmosis systems so that they might consume the freshest water possible from the tap. Reverse osmosis is simply a system of filtration that eliminates different molecules and ions out of the water. This removal of unwanted particles happens when the water passes through a permeable membrane that has small holes. This permeable membrane helps to stop particles like chlorine, metals, and fluoride from getting into the water we consume, thus creating a purer taste. Under the sink reverse osmosis systems are the most popular osmosis systems there are.