CH4, or methane, is comprised of one carbon atom and four hydrogen atoms. The bonds formed between these atoms are covalent bonds. This occurs because both carbon and hydrogen tend to share electrons rather than transfer them. In a covalent bond, atoms achieve stability by sharing electrons in their outer shell.
Specifically, carbon has four electrons in its outer shell and needs four more to fulfill the octet rule, while hydrogen has one electron and needs one more to achieve a stable configuration. Therefore, carbon shares its four electrons with four hydrogen atoms, leading to the formation of four strong covalent bonds. This electron sharing characteristic is what defines covalent bonding and distinguishes it from ionic bonding, where electrons are transferred from one atom to another. Hence, CH4 consists solely of covalent bonds, contributing to its stability and unique properties.