Waves A Wave is any periodic fluctuation traveling through a medium that carries energy.
Speed depends on water depth, salinity, etc.
Light as electromagnetic waves Can treat light as an Electromagnetic Wave Fluctuation in the intensity of electric and magnetic fields. Travels through a vacuum at the speed of light. The wavelengths given in the table above are only approximate. Color is a physiological response of our brains to light of different wavelengths. I include approximate wavelengths primarily for purposes of illustration.