You need to turn in a thesis prospectus for obtaining a MS or PhD degree. The department has official guidelines as of what to turn in and such.
In terms of content, both MS and PhD prospectus need to discuss the research to be conducted (literature review, proposed methods, etc). In addition, the PhD prospectus also requires you to propose the courses you are going to take (refer to Course & Degree Requirements for info on the major and minor courses).