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How does a carbon-halogen bond make an organohalogen compound polar?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — halogen Modern version of the periodic table of the elements.

A carbon-halogen bond makes an organohalogen compound polar due to the difference in electronegativity between the carbon atom and the halogen atom.12

Electronegativity is the ability of an atom to attract shared electrons toward itself within a chemical bond. Because the halogen atom is more electronegative than the carbon atom, it draws the shared electron pair closer to itself. This unequal sharing of electrons results in the halogen acquiring a partial negative charge and the carbon atom acquiring a partial positive charge.12

The presence of these equal but opposite partial charges at the ends of the bond creates an electric dipole, which is characterized by a dipole moment. This dipolar character is what renders the carbon-halogen bond polar. Whether the entire molecule is polar depends on its overall shape and whether these individual bond dipoles cancel each other out.12