You may have noticed that the books in the library collection have letter and numbers assigned to them, this is called a Title ID. The Title ID is a unique number proceeded by two or three letters. They can be found in Talking Book Topics and the library’s online catalog. Many library borrowers use these IDs when requesting books from the library. Libraries use 
Title IDs to add requests to patron accounts and to know where a book is located on the library’s shelves.
Here are some examples of what these letters and numbers mean; DB at the beginning means it is a digital book and BR at the beginning means it is a braille book produced by the National Library Service for the Blind and Physically Handicapped (NLS). There are other prefixes that you might see as well. A DBC and a BRC are books that were produced by cooperating libraries in the NLS network. So, books that our library produced and made available to the network have the DBC or BRC Title ID. An M indicates the book is part of the NLS Music collection, which consists of music scores, music instruction, and books about music. DBO indicates a book that our library has recorded, but has not made available to other libraries in the NLS network. BRN indicates a Braille book that the library has purchased from a vendor for the collection.
Here is a quick look at the Title IDs you might see in the library’s online catalog and what they can tell you about the book:
DB – Digital Book
BR – Braille Book
LT – Large Type Book
KIT – coming soon and will be used for early literacy kits that will be available for check out
3D – coming soon and will be used for 3D tactiles that will be available for check out