Here's why:

* Electronic Configuration: Carbon has an electronic configuration of 1s² 2s² 2p². This means it has 4 electrons in its outer shell (2s and 2p orbitals).

* Octet Rule: Carbon wants to achieve a stable octet (8 electrons) in its outer shell.

* Covalent Bonding: Carbon achieves this by forming 4 covalent bonds with other atoms. It shares its 4 valence electrons with other atoms, allowing both atoms to achieve a stable octet.

This is why carbon forms a wide variety of molecules, from simple methane (CH₄) to complex organic molecules like proteins and DNA.