Mg, or magnesium, is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray solid that is part of the alkaline earth metals group. Magnesium is essential for many biological processes and is found in various foods, including green leafy vegetables, nuts, and whole grains. In nature, magnesium is commonly found in minerals such as magnesite and dolomite. It plays a crucial role in the production of energy within cells and is important for muscle function and bone health. Magnesium is also used in various industrial applications, including the production of lightweight alloys and fireworks.