Water is an inorganic compound with the chemical formula H2O. It is a transparent, tasteless, odorless, [c] and nearly colorless chemical substance. It is the main constituent of Earth's streams, lakes, and …

Jun 8, 2026 · Water, substance composed of the chemical elements hydrogen and oxygen and existing in gaseous, liquid, and solid states. It is one of the most plentiful of compounds and has the …

Within the Earth's atmosphere and surface, the liquid phase is the most common and is the form that is generally denoted by the word "water". The solid phase of water is known as ice and commonly …

Welcome to the science section of the USGS Water Science School, where you can explore the many aspects of water. All of our information is available by browsing the various categories below.

5 days ago · Water (H₂O) – Definition, Structure, Preparation, Uses, Benefits Water is a chemical compound made of hydrogen and oxygen essential for all forms of life. It supports ecosystems, …

All living things, from tiny cyanobacteria to giant blue whales , need water to survive. Without water, life as we know it would not exist. And life exists wherever there is water. All organisms, like animals and …

Jan 28, 2026 · Not only does water make up most of your weight, it’s involved in many important functions. See how water improves your overall well-being.

Feb 27, 2024 · In its purest form, it's odorless, nearly colorless and tasteless. It's in your body, the food you eat and the beverages you drink. All forms of life need it. What substance is more necessary to …

Dec 23, 2025 · Water is in constant movement across our planet. The water cycle shapes our weather and climate patterns & provides freshwater that supports all life on Earth.Observing and monitoring …

Aug 1, 2025 · Looking at water, you might think that it's the simplest thing around. Pure water is practically colorless, odorless, and tasteless. But it's not at all simple and plain and it is vital for all life …