The Graduate Record Examination (GRE) is the preferred test that the Admissions Committee uses to evaluate all graduate students. Be conscious of the times that this test is offered since you must have the scores reported to the Graduate School prior to the deadline for admission. Hence, prepare to take this early.
There are three parts that the Admissions Committee looks at: verbal, quantitative, and analytical scores. In the past, applicants admitted typically score 500+ for the verbal and 600+ for the quantitative sections of the exam. Analytical scores are 4.5 and above.