Depending on your skill level, there may be several purposes. After a few term papers, your organizational skills and writing ability will improve. You will also ask better questions about readings and be better able to see relationships between ideas and approaches in different sources. Term papers are excellent practice for writing reports, both for the business world and for research. With practice, editing, and lots of hard work, they are also good springboards to develop your own creative thought.
Many parallels exist between writing a term paper and the daily work of a scientist.
Start with a topic area. The topic can be narrowed or changed once you have an idea of the availability of references. Generally, your OS instructors will want you to use both textbooks and journal articles as references. You should turn first to your course text and other textbooks for a general understanding of your topic, before searching for other references. The textbooks will help you to read the papers you find later.