Step 1 - What is a polar bond?
A polar bond is any bond formed between atoms which have an electronegativity difference.
Electronegativity is a propertie that determines how strongly can an atom attract electrons.
Therefore, when atoms of very different electronegativity bond together, the electrons of the chemical bond will be closer to the most electronegative atom.
The most electronegative atoms are F, O and N.
Step 2 - Example of polar bonds
Some polar bonds are: