Here's why:

* Electronegativity is the measure of an atom's ability to attract electrons towards itself in a chemical bond.

* Polar covalent bonds occur when there is a significant difference in electronegativity between two atoms. This difference causes the electrons to be unequally shared, creating a partial positive charge on one atom and a partial negative charge on the other.

Examples:

* The bond between oxygen (high electronegativity) and hydrogen (low electronegativity) in water (H₂O) is a polar covalent bond. The oxygen atom pulls the shared electrons closer to itself, making it slightly negative, while the hydrogen atoms become slightly positive.

In contrast:

* Nonpolar covalent bonds occur when the electronegativity difference between two atoms is very small or zero. The electrons are shared equally.

* Ionic bonds form when there is a large electronegativity difference, leading to one atom essentially giving up an electron to the other, creating a full positive and a full negative charge.

So, while electronegativity is a property of individual atoms, it directly influences the type of bond formed between them, with polar covalent bonds exhibiting the highest electronegativity differences.