Light polarization is a property of light waves that depicts the direction of their oscillations. A polarized light vibrates or oscillates in only one direction. This is in contrast to a nonpolarized light that vibrates in many directions. A polarized light may be plane-polarized, circularly polarized or elliptical-polarized light based on the net direction of the vibrations.
Many animals are able to perceive and use certain forms of polarized light. For instance, insects use plane-polarized light for navigational purposes. A naked human eye is not very sensitive to polarized light but with practice, or with the use of a polarizer, humans can then perceive a polarized light such as the Haidinger's brush phenomenon.