Write the types of dielectrics and explain them. Give some examples of dielectric substances.

(N/A) Dielectrics are classified into two types based on the nature of their molecules:
$(1)$ Polar Dielectrics: In a polar molecule,the center of the positive charge and the center of the negative charge do not coincide with each other. Such molecules possess a permanent electric dipole moment even in the absence of an external electric field. Examples: $H_{2}O$,$HCl$.
$(2)$ Non-polar Dielectrics: In a non-polar molecule,the center of the positive charge and the center of the negative charge coincide with each other. Such molecules do not possess a permanent electric dipole moment in the absence of an external electric field. Examples: $O_{2}$,$H_{2}$,$CO_{2}$.