LASER is the acronym for Light Amplification by Stimulated Emission of Radiation.
The physical principle described in this statement is generation of a light beam with very particular characteristics. A laser beam is in fact monochromatic, coherent, unidirectional and collimated, these characteristics allow it to become an irreplaceable tool in industrial production, scientific research, telecommunications or medicine.
LASER is a physical principle and not a technology, there are wide range of lasers, the active medium determines the laser wavelength and consequently the interaction with any materials. Each type of laser is the optimal choice for a specific application or for use on a specific material.