How do polar and nonpolar covalent bonds and polar and nonpolar molecules compare? how do they contrast?

Compare and contrast between bonds and molecules of polar and non-polar:Non-polar covalent bonds are a type of covalent bond in which a pair of electrons is shared with each other between two atoms. Polar covalent bond is a type of covalent bond in which pair of electrons are not equally shared between two atoms. We can also say bonds are polar when one element in a compound is more electronegative than the other.  The bond shared in the compound of carbon dioxide between carbon and oxygen atoms is non-polar covalent bond whereas the shared in the compound of water between hydrogen and oxygen atom is polar-covalent bond.  Polar molecules are those molecules where there is an “electronegativity difference between the bonded atoms”.  For eg: Water - , Ammonia - , Sulfur dioxide - , Hydrogen sulfide - , Ethanol - , etc.  Non-polar molecules are those molecules sharing equal electrons between “atoms of a diatomic molecule” or large molecule cancel each other. For eg: Carbon dioxide - , Benzene - , Carbon tetrachloride - , Methane - , Ethylene - , etc.

There are no metaphors.