Before computer databases were available to keep the catalog records of library holdings, a library card system was used. Public catalogs filled with these card were available in the library for browsing. The cards for books and other material were organized and accessible by title, author and subject in separate catalogs. Some of these old card catalogs are still available for use on the first floor of Crerar.
In addition print indexes in the form of books, usually issued yearly, were used access to articles in journals by article title, author and subject.
Book borrowing cards were also used to keep track of borrowed materials before the advent of computer systems. When a book was checked out the borrowers name was noted and the card was removed and held by the library. The cards were held to keep track of what books have been taken out and by whom. The Library no longer uses these cards but their pocket holders are still visible in the back of some of the older books in Crerar.