Light therapy involves the use of different kinds of light to treat various physical problems or conditions. The light can be visible to the human eye (i.e. within the visible spectrum) or it can be non-visible as in the case of ultraviolet light. Sometimes called phototherapy, light therapy is used to treat sleep problems, acne problems, mood disorders, and more.

Light, especially sunlight, has long been known to have healing powers, but it wasn't until the 1980's that science began discovering how specific wavelengths of light could have specific positive effects on human physiology, especially the skin. For instance, today narrowband light is used to treat several skin conditions like acne, psoriasis, eczema, and vitiligo. And light therapy has also found its way into the cosmetic world as an effective method for skin rejuvenation.