The Books & Media profile (marked on the library website front page by the "books, music, video" tab) acts as the default interface to the catalog for the majority of users.  The ways in which searching and results differ between the EDS interface and the native Ex Libris/Aleph interface are partly enumerated below.

EDS Books & Media includes more than the UMBC catalog, but less than the USMAI catalog

The Books & Media profile, in addition to the UMBC catalog, includes results from Alexander Street Press and Naxos Music.  It also includes EBSCO Ebooks as a separate collection, even though those ebooks are included in the catalog.  Because Ebsco Ebooks have a lag time before cataloging, this may result in their being represented at a slightly higher volume in EDS on average, but this difference should not be significant. 

The catalog included in the Books & Media profile is only the UMBC portion of the USMAI catalog (represented in the profile databases as 'cat01476a') - which, in terms of intra-USMAI library loan for monographs, makes it a fundamentally different experience than interacting with the USMAI catalog interface.  This was a deliberate decision made by Reference and others, who wanted the Books & Media profile to provide immediately-available resources to the UMBC user.

To provide an idea of the difference between EDS, UMBC catalog and USMAI catalog, a search for 'America' with no limiters results in the following pattern (figures rounded):

Of course, it is important to remember that the significantly higher total returned by the USMAI Catalog includes generally non-lendable items such as videos or archival materials.  An interesting dynamic in the catalog (and reflected in EDS) is that even when, for instance, the entire USMAI catalog is limited to 'book' format, 'America' still returns 144,000.  However, this number is significantly inflated by results of online GPO records, many of which are dead links.

Search limiter options are different (and somewhat fewer) in EDS compared to the catalog

The catalog provides a greater number of format limiters, and it provides 'location' limiters (e.g. Reference, Special Collections) that EDS doesn't present at all.  These catalog-only limiters, it should be noted, need to be prepended to searches (unless the user is prepared to limit by command-string variables, which even Reference librarians rarely use), whereas EDS follows the model of 'search first, limit later.'  This fundamental difference in search method is something that Reference librarians need to address.