Teaching methods comprise the principles and methods that are used by teachers to facilitate learning by students. Strategies are determined both by the subject matter to be taught and the characteristics of the student. While today's schools encourage creativity, this was not always the case. Tudy Guides are books can be used by students to enhance or speed their comprehension of literature, research topics, history, mathematics or many other subjects. Topics that may be contained in a Study Guide include study and testing strategies: reading, writing, classroom, and project management skills. For example, in literature some study guides will summarize chapters of novels or the important elements of the subject. In the area of math and science study guides generally present problems and offer alternative techniques for the solution."