The Library keeps a variety of collections within its shelves of books. Non-fiction is one of these, and it is split into JNF (Juvenile Non-Fiction) and ANF (Adult Non-Fiction). We also have fiction, however it breaks up into a lot more collections - AF (Adult Fiction), JF (Juvenile Fiction), APB (Adult Paperback), LF (Large Print Fiction), etc.
Across all of these fiction collections, though, the Library puts on the spine of many a label to indicate their broad genre, to help you find books of a type you might want to read.
An additional identifier not pictured above is a green dot, which is attached to Large Print books. Please note, there is no requirement to be vision-impared to check out and read large print books. Many people find they can simply read them faster. In fact, it's worth checking out all of the sections of the Library's collection. There's young adult and juvenile novels that are well worth reading and a lot of fun for adults!