Why are the oxygen-hydrogen and carbon-oxygen bonds in alcohols polar?

The oxygen-hydrogen (O–H) and carbon-oxygen (C–O) bonds in alcohols are polar because of the differences in electronegativity between the atoms involved.1

Electronegativity is a measure of an atom's ability to attract shared electrons toward itself within a chemical bond. Oxygen is significantly more electronegative than both carbon and hydrogen. Consequently, in these bonds, the oxygen atom draws the shared electron pair closer to itself, acquiring a partial negative charge. Conversely, the carbon and hydrogen atoms, having lost a greater share of the bonding electrons, acquire partial positive charges.21

This unequal distribution of electrical charge creates a dipole, which is the defining characteristic of a polar bond. These polar bonds within the hydroxyl group are responsible for many of the physical and chemical properties of alcohols, including their ability to form hydrogen bonds and their solubility in water.213