In the graduate school admissions process, the level of emphasis that is placed upon GRE scores varies widely between schools and even departments within schools. The importance of a GRE score can range from being an important selection factor to being a mere admission formality.
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GRE Subject Tests
In addition to the General Test, there are also eight GRE Subject Tests testing knowledge in the specific areas of Biochemistry, Cell and Molecular Biology, Biology, Chemistry, Computer Science, Literature in English, Mathematics, Physics, and Psychology. In the past, subject tests were also offered in the areas of Economics, Revised Education, Engineering, Geology, History, Music, Political Science, and Sociology. In April 1998, the Revised Education and Political Science exams were discontinued. In April 2000, the History and Sociology exams were discontinued, and the other four were discontinued in April 2001
Preparation
A variety of resources are available for those wishing to prepare for the GRE. Upon registration, ETS provides preparation software called PowerPrep, which contains two practice tests of retired questions, as well as further practice questions and review material. Since the software replicates both the test format and the questions used, it can be useful to predict the actual GRE scores. ETS does not license their past questions to any other company, making them the only source for official retired material. ETS used to publish the "BIG BOOK" which contained a number of actual GRE questions; however, this publishing was abandoned. Several companies provide courses, books and other unofficial preparation materials.