Light works when photons, which are small packets of energy or units of electromagnetic radiation, travel in electromagnetic waves throughout space. Light makes things visible, enabling organisms to see.
Light makes things visible, due in part to wavelength and frequencies. Light travels in electromagnetic waves that have different sizes when measured from wave hump to wave hump. Humans can only naturally see when light is in the visible spectrum with wavelengths between 400 and 700 nanometers.
Light also has a frequency, which is how many waves pass a certain point in a certain amount of time. Visible light has a frequency between 430 and 750 trillion hertz per second. The different frequencies in the visible spectrum show up as colors. For instance, the lowest frequency of light appears as a red color while the highest appears as violet.
The electromagnetic spectrum includes wavelengths and frequencies beyond visible light such as ultraviolet and infrared rays that cannot be seen through natural means. The longest and lowest frequencies of light are radio and microwaves while the highest are x-ray and gamma rays.
Scientists believe that light has properties of both a particle and a wave. When a light wave encounters an object, it behaves as a particle or photon.