Pg means post graduation,which is done after you complete your under graduation course. Phd is the degree of doctorate in any subject which means it is the highest graduation degree .Pg is a course of usually two years while phd is a course which has a duration of three years.
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Hi

A graduate degree requires a significant investment of time. Pg require less time than doctoral degrees. Typically a full time student might acquire Masters degree in about two years.
A PhD usually requires at least five to six years and many people take seven to nine years

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