Reverse osmosis (RO) is a water filtration process that removes contaminants by forcing water through a semipermeable membrane. It effectively eliminates impurities such as dissolved salts, bacteria, viruses, and chemicals, making it a popular choice for drinking water purification. RO systems typically include multiple filtration stages, such as sediment and carbon filters, to enhance water quality. While highly effective, RO can waste some water during the filtration process and may remove beneficial minerals, requiring remineralization in some cases.