What is GRE test ? and what are requirments for this exam ?

The GRE® (Graduate Record Exam) Test is the standardised test used to fetch admissions in various graduate schools or business graduate schools in various countries, especially the United States. More than 100,000 graduate school applicants from approximately 160 countries take the GRE General Test at 700 test centres. Aspirants interested in pursuing a master's degree, specialised master's course, MS, MBA, MEM or doctoral degree can sit for the GRE Test. In addition to the GRE revised general test, there are six GRE subjects tests that evaluate candidates’ knowledge in their respective field. GRE test is conducted by ETS®(Educational Testing Service).