Lasers come in many different colors and are used worldwide for many different purposes. Red and green are only two of those colors, and as can be found through further research, "red" and "green" are actually two very subjective descriptions when it comes to lasers.

                                                             

What is a Laser?

A laser is an organized beam of light. It can be thought of it like this: organized line of marching soldiers versus a group of panicking people. The term laser actually stands for Light Amplification by Stimulated Emission of Radiation.

Wavelengths of Lasers

Laser beams are gauged in nanometers, which tells you how thick the beam is. Red lasers are 650 nm, and green lasers are 532 nm.

Laser Power Levels

A laser's power is gauged in the watt scale: milliwatts, watts, kilowatts, megawatts and so on. Laser pointers are in the milliwatt scale, up to 1 mW.

Uses of Red Lasers

Typical red laser uses are in CD and DVD readers and players in the home either for TV or PC use. Red lasers are also used for digital audio output via TOSLINK cables for high-fidelity digital audio.

Uses of Green Lasers

Typical public uses for green lasers are for more powerful astronomical laser pointers, or in rock concerts and other types of music for laser-light shows.