A working bibliography is a preliminary, ongoing record of books, articles, and other sources of information that you discover as you research your subject. A final bibliography is lists only sources actually used in your paper. Some sources in your working bibliography may turn out to be irrelevant, while others may simply be unavailable. But you need to carefully document what sources you've consulted or looked for, in case you have to return to them again later on.
Different disciplines require different documentation styles.
Your MLA handbook provides you with detailed information on how to use this documentation style for your research. Also from the Library Home Page, go to Handouts and then look for Style Guides and Citations. You will find lots of additional information on MLA Documentation, including how to document electronic resources. Often students cannot find information on their topic because they are not using the correct terms in their search. To research a subject, you need to know how it is classified, what key words are used as subject headings in encyclopedias, bibliographies, the MLA database, and the card catalog.