They are both ways to obtain books from other libraries. If a book is owned by one of the other I-Share libraries in Illinois, then patrons are required to request from them first. The patron requests the book directly from the online catalog (I-Share Catalog). If the book is not available, or has been requested and not filled by an I-Share library, then patrons may request it through Interlibrary Loan (ILL). The Interlibrary Loan (ILL) department will then request the book from libraries outside the I-Share system. (If requested and unfilled from I-Share, please indicate this in the comments section of the Interlibrary Loan (ILL) request form.)