Water is a liquid made of hydrogen and oxygen that exists in liquid, solid, and gas forms. Most water is in the oceans, while fresh water is found in lakes, rivers, and glaciers. Water is essential for human life as it transports nutrients through the body and aids digestion, and is important for agriculture and industry. Though less than 1% of water is available for human use, factors like global warming and industrial pollution are depleting supplies, so conservation methods like fixing leaks, limiting showers, and treating wastewater are recommended.