While the history and what a LASER is, what's very interesting are non-optical LASERs. Some are pretty scary.
Charles H. Townes is said to have created the MASER in 1951 (Wikipedia) which means that almost all EM sprectrum outputs have been tried over the years.
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation What is the full form of LASER
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