The Graduate Record Examination
Although there has been much discussion about the predictive value of GRE scores, it is still required and used by most schools in the evaluation of the admissions file. The weight placed on the GRE varies from school to school. Therefore, it is essential that you do well on this examination. There are many resources available to help you prepare for the GRE including practice tests and preparatory courses offered by companies.
This official website of offers general and detailed information about the GRE, sample questions, test-taking tips, registration information, etc.