Oxygen is required by all living things for respiration. It's also used in industries, water treatment, burning fuels and even protecting humans from harmful UV light thanks to the ozone layer.
Oxygen is a colorless, odorless and tasteless gas. It comprises 22 percent of air in the atmosphere and is part of the air that people breathe. Oxygen is found in the atmosphere, the human body, the sun and oceans.
The most important use of oxygen is sustaining life. All living organisms require oxygen to survive. Through aerobic respiration, energy is generated from food, allowing organisms to carry on with their daily activities. Oxygen is usually used in health care institutions to aid breathing in people with respiratory problems.
The main commercial application of oxygen is steel production where oxygen reacts with steel to remove carbon impurities. Oxygen is also used in ethylene and methanol production, in oxyacetylene welding, and to oxidize rocket fuel.
Oxygen is essential for all combustion processes, such as burning of fuels (oil, petrol, natural gas, coal), which heat homes and power vehicles. Fires need oxygen to burn, and one way to put out fires is to remove oxygen by smothering it or using carbon dioxide.
As well as these uses, oxygen is used by scuba divers, mountaineers and astronauts. It is also used in glass making, water treatment, petroleum processing, destroying bacteria, ceramic production and pulp and paper production.