Phosphorus is a non-metallic chemical element with atomic number 15, existing primarily as white phosphorus (P4) in its common allotrope. In mineral form, it occurs in phosphate rocks and is vital for biological processes including DNA/RNA structure, ATP energy transfer, and skeletal mineralization. White phosphorus is a waxy, yellowish solid that ignites spontaneously in air. It is not directly used in food but serves as a precursor for phosphates in nutrition and agriculture. The element plays a critical role in cellular metabolism and is obtained through dietary sources like meat, dairy, and grains in the form of phosphates rather than elemental phosphorus.