Put simply, bottled water is water that has been collected from a natural source and then packaged in a bottle for human consumption. Bottled water can come from underground sources (spring water) or surface sources (like lakes or rivers). Most commercial bottled water companies get their water from springs since it is well known to be clean and safe for drinking. Moreover, the water undergoes a filtration process to remove any impurities before it is bottled. This process usually includes reverse osmosis, ultraviolet light treatment, and ozone disinfection. By these means, almost all bacteria and viruses are removed from the water to ensure that it is safe for human consumption. People tend to purchase bottled water for a variety of reasons. Some people believe that it tastes better than tap water, while others think it is more convenient or safer to drink. Moreover, in some parts of the world, the local tap water is not safe to drink due to high levels of contamination. In these cases, bottled water is the only option.