Chemical bonds are the links which hold the atoms either of the same element or atoms of different elements. There are three types of bonds-
Covalent bond- These bonds are formed between two non-metals by the sharing of valence electrons.
Ionic bond- These bonds are formed between a metal and a non- metal by transferring of valence electrons.
Metallic bonds-The type of chemical bond between atoms in a metallic element formed by the valence electrons moving freely through a metal lattice.
Always remember that a chemical bond will form only in these three cases.
Also do not get confused between ionic and covalent bonds because in covalent bonds valence electrons are shared because both the non-metals are the needy ones and in ionic bonds valence electrons are transffered because one atom has extra valence electrons and the other needs them.