Water is the most abundant compound on Earth's surface, covering about 70% and is essential for all life on Earth. Hence reducing the usage of water, conservation and recycling of waste water for different purposes  is of utmost importance. It primarily consists of following subsectors: 1 Water Treatment Process for enhancing the quality of water so that it meets the water quality criteria for the intended use. Such treatment grew vastly in importance in the 20th century because of the growth of cities and development of industry and, consequently, of pollution 2 Water Storage & conservation Is a practice which attempt to store and conserve water, reduce water usage and prevent loosing usable wate 3 Rain Water Harvesting Rainwater harvesting is the collection and storing of rainwater for reuse. This water can be used for drinking, irrigation and other normal use of water. 4 Water Desalination Removal of salt and other minerals from the sea water to make it suitable for human consumption or industrial use. 5 Water Quality Measurement Measurment of condition of water relative to the purpose of it usage i.e for drinking or industrial purpose etc.