Lens hoods are used to absorb strong light that falls sideways on the lens (sunlight) and to prevent the light from causing unwanted reflections or diffractions in the lens system (and thus on the resulting image). Protecting the lens is not the primary objective of lens hoods. Most photographers use a UV filter or a polarizing filter for protection purposes. Someone correct me please if I got it wrong. :unsure:

We do not see things as they are. ǝɹɐ ǝʍ sɐ sƃuıɥʇ ǝǝs ǝʍ