Before we can learn about the laser we need to know a little bit about
             light (since that is what a laser is made of). Light from our sun, or from an
             electric bulb, is called white light. It is really a mixture of all the different
             colours of light. The colours range from violet, indigo, and blue, to green,
             yellow, orange, and red. These make up the visible part of the
             electromagnetic spectrum. Light is made up of particles, called PHOTONS,
             which travel in waves. The difference in the colour depends on the
             wavelength of the light. Violet light has the shortest wavelength while red has
             the longest. There are other parts of the electromagnetic spectrum which
             includes infra-red, radar, television radio and micro- waves (past red on the
             spectrum), and on the other end of the spectrum are the other invisible
             radiations, ultra- violet, X rays, micro waves and gamma rays. The
             wavelength of the light is important to the subject of the laser. A laser is made
             up of COHERENT light, a special kind of light in which the wavelengths of
             the light are all the same length, and the crests of these waves are all lined up,
             or in PHASE. The word Laser is an acronym for Light Amplification by
             Stimulated Emission of Radiation. What does that mean? Basically a laser is a
             device which produces and then amplifies light waves and concentrates them
             The principles of the laser (and it's cousin the maser) were established
             long before these devices were successfully developed. In 1916 Albert
             Einstein proposed stimulated emission, and other fundamental ideas were
             discussed by V.A. Fabrikant in 1940. These ideas, followed by decades of
             intensive development of microwave technology set the stage for the first
             maser (a laser made up of micro-waves), and this in turn helped to produce
             more advances in this area of science. These efforts cumulated in July 1960
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