Lithium burning is a special way that stars burn, or use, their fuel. A star is like a very big ball of gas, and gases in stars are made up of smaller particles called atoms. In order to keep a star shining and hot, it needs fuel, and the fuel usually comes from atoms like hydrogen and helium. But in some special stars, called Red Giant stars, the fuel sometimes comes from a different type of atom called lithium. Lithium is special because it can burn in a really bright way and it helps the star look really bright, like a giant sparkler.