Reverse osmosis (RO)system is a water purification process that uses a partially permeable membrane to separate ions, unwanted molecules, larger particles and colloid, organic impurity, heavy metal ion from drinking water. 

Reverse osmosis system can remove many types of dissolved and suspended chemical species as well as biological ones (principally bacteria) from water, it is also effective with asbestos, many taste, color and odor producing chemicals, particulates, total dissolved solids, turbidity and radium, is used in both industrial processes and the production of potable water.