From Youtuber snuggliepuppy:

Chemical bonds are what hold atoms together. A chemical bond is an attraction between atoms that allows the formation of chemical substances. The electrons that participate in chemical bonds are the valence electrons, which are the electrons found in an atom’s outermost shell.

An ionic bond is formed when one of the atoms will lose its electron to the other atom. This results in a positively charged ion, called an cation. and negatively charged ion, called an anion. Positive and negative attract! The result is ionic bond.

Covalent chemical bonds involve the sharing of a pair of valence electrons by two atoms

There are also what is called Polar Covalent Bonds. These are Covalent bonds in which the sharing of the electron pair is unequal. The result is a bond where the electron pair is displaced toward the more electronegative atom.

[Via Neatorama]