gre is an exam its stands for graduate record examination. based on this exam you can do master course in usa and some other countries.
i am providing you gre website where registration and other information is available.
https://www.ets.org/gre/revised_general/register
Eligibility | Application | Exam Centre | Exam Pattern | Preparation Tips | Result | Cutoff
Eligibility | Application | Exam Pattern | Preparation Tips | Result | Exam Centre | Dates
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