As a UCLA student, you have so many resources available to you that there are three catalogs to keep track of them all! Don't worry, though—finding what you need is simple once you learn the system.
The catalog you'll probably use most often is the UCLA Library Catalog. This catalog will point you to books, movies, journals, and other resources at the UCLA Library.
Melvyl is a catalog shared by the entire University of California library system. This means that if you search for something in Melvyl, you'll not only see where it's at in the UCLA Library, but at Berkeley, Irvine, and all the other campuses. If UCLA doesn't have something you need, you can have it sent from another campus by clicking the orange "request" button. Melvyl also searches articles, but we recommend you use an article database unless you know the exact title and author of an article.
Melvyl is the UC's portal into WorldCat, which is a gigantic catalog shared by thousands of libraries across the globe. When you search WorldCat, you can see all the public and university libraries that have an item.