Wow. A student asked how to do this, so I dug in just a bit.
To find this for yourself, start Word. Click on the Help button (blue circle with a question mark) and search for: citation. I then clicked on the link for APA, MLA, Chicago – automatically format bibliographies.
In Microsoft Word 2007 and Word 2010, you can automatically generate a bibliography (or other similar document requiring citations) of the sources you used to write your paper. Each time you add a new citation to your document, Word adds that source so that it appears in the bibliography in the proper format, such as MLA, APA, and Chicago-style.