What is a Laser?
The word "LASER" is an acronym and stands for "Light Amplication by Stimulated Emission of Radiation".  We explain this fully in our "Shedding Light on Lasers" seminar.   
A laser is a beam of light.  Think of its beam as the light from a standard flashlight.  The beam of light either bounces off a material like light bouncing off a mirror OR the light will absorb into a material like water absorbing into a sponge under running water from a kitchen sink.  The by-product of laser processing is smoke from the material that must be exhausted either outside or through a fume system.    

Below is the entire light spectrum.  The visible section is light we can see with our eyes.  You can see that only one of the laser wavelenghs that we use for marking falls in this range.  

As with any laser, eye-protection is critical.  This is still the case with the Green laser.  A visible light does not exclude the need for eye protection as the light is very intense and could cause permanent eye damage to the retina.  

It is standard for laser companies to sell eye-safe workstations.  These are Class 1 or Class 2 rated.  

One question that arises is the need for radiation protection.  A laser process does NOT emit radiation in a way that extra protection is needed.  Radiation is part of the acronym in "LASER", but it is simply a beam of light that heats a material to cause processing.