The element with the chemical symbol "O" is oxygen. Oxygen is a vital element for life on Earth, crucial for respiration in many living organisms. It is a colorless, odorless gas at room temperature and makes up about 21% of the Earth's atmosphere. Oxygen readily forms compounds with nearly all other elements and plays a significant role in combustion processes. In addition to its importance in biological respiration, oxygen is essential for cellular metabolism. Moreover, oxygen is widely used in various industrial applications, including manufacturing steel and in medical settings for patients requiring respiratory support.