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Luminescence is the generation of light without heat. There are two principal varieties of luminescence, fluorescence and phosphorescence, distinguished by the delay in reaction to external electromagnetic radiation. The ancients observed phosphorescence in the form of a glow emitted by the oceans at night, and confused this phenomenon with the burning of the chemical phosphor, but, in fact, phosphorescence has nothing at all to do with burning. Likewise, fluorescence, as applied today in fluorescent lighting, involves no heat—thus creating a form of lighting more efficient than that which comes from incandescent bulbs.http://www.scienceclarified.com/everyday/Real-Life-Chemistry-Vol-5/Luminescence.html#b 

A laser is a device that emits light (electromagnetic radiation) through a process of optical amplification based on thestimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation.^[1][2] The emitted laser light is notable for its high degree of spatial and temporal coherence. http://en.wikipedia.org/wiki/Laser