Phosphorus, (IPA: , Greek: phôs meaning "light", and phoros meaning "bearer"), is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus is commonly found in inorganic phosphate rocks.
Due to its high reactivity, phosphorus is never found as a free element in nature. One form of phosphorus (white phosphorus) emits a faint glow upon exposure to oxygen (hence its Greek derivation and the Latin light-bearer meaning the planet Venus as dawn-bearer or "Morning Star").
Phosphorus is a component of DNA and RNA and essential element for all living cells. The most important commercial use of phosphorus-based chemicals is the production of fertilizers.
Phosphorus compounds are also widely used in explosives, nerve agents, friction matches, fireworks, pesticides, toothpaste, and detergents.