Check for books on Reserve at the Circulation Desk. The loan period is determined by the professor (for instance, a book may be checked out for 2 hours in-library use, while a DVD could be checked out overnight). A staff member at circulation will notify you of the time limit.
You can check to see if your professor has put books on Reserve by searching under the Course Reserve link at the Online Catalog. From this page you may search by Instructor, Department, Course, and Section.
Faculty, please find the instructions on how to put an item on reserve here.