Earth is the third planet from the Sun and the only known celestial body to support life. It has a diverse range of ecosystems, from lush forests to arid deserts, and is home to millions of species, including humans. The planet's atmosphere is composed mainly of nitrogen and oxygen, which are essential for life. The Earth's surface is covered by approximately 71% water, primarily in the form of oceans. This vast body of water plays a crucial role in regulating the planet's climate and supporting marine life. Additionally, Earth has a rich geological history, with tectonic plates constantly reshaping its landscape.