Permittivity is a physical quantity that describes how much a material can store electric field energy. It is a measure of a material's ability to permit the flow of electric field lines through it.

Common units related to permittivity include Farads per meter (F/m) and relative permittivity (also known as dielectric constant), which is a dimensionless quantity.

• Permittivity is crucial in the design of capacitors and insulators
• It determines the speed at which electromagnetic waves travel through a medium
• Helps in understanding the behavior of electric fields in different materials