what is E.D.M machine ?

EDM:Electric Discharge Machining
Electric Discharge Machining is a process that utilizes an electrode to create a hole or threads in a hardened ball.

EDM:Electronic Distance Measurement
Electronic Distance Measurement device, the instrument used by modern surveyors that replaces the use of measurement chains. It determines distance by measuring the time it takes for light to reflect off a prism on top of a rod.

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