LASERs, which stands for Light Amplification (by) Stimulated Emission (of) Radiation, were developed in 1960 by Theodore Maiman. Lasers were quickly adopted for ophthalmology with the first instance of their clinical use appearing in 1963. Over the last 50 years ophthalmic lasers have proliferated in both types of lasers and indications. Despite this diversity, all lasers function on the same fundamental principles. Lasers are created when the electrons in atoms in special glasses, crystal or gases absorb energy from an electrical current or another laser and become excited/elevated to a higher energy state. Electron orbits are less stable at these higher energy states, thus energy is released in the form of a photon which allows the electron to return to its ground state. Photons are particles of light, however, what makes laser photons unique is that they are all of the same wavelength, directional, and coherent (meaning the crests and troughs of the light waves are aligned) whereas ordinary light comprises multiple wavelengths and is not coherent.