Polar bonds

Polar bonds are covalent bonds between atoms with a difference in electronegativity between 0.4 and 2.0 on the Pauling scale. The shared electron pair is distributed unequally between the two atoms, resulting in partial charge on the two atoms: A partial negative charge on the more electronegative atom and a partial positive charge on the less electronegative atom. The bond is said to be polarized towards the more electronegative atom.

See some examples of polar bonds in organic chemistry.