Why carbon form millions and billions of compound?

Answer 1

Carbon forms so many compounds because each carbon atom is able to form stable chemical bonds with up to four other atoms.

Answer 2

Carbon is unique because of its ability to form strong covalent bonds with other elements, resulting in a wide variety of compounds. Its ability to form single, double, and triple bonds allows for structural diversity in molecules. Additionally, carbon can form long chains and complex three-dimensional structures, contributing to the vast number of carbon-containing compounds known as organic compounds.