Shelfcodes

A shelfcode is used to describe the type of book in the library, and which section it can be found in. They consist of three optional parts, always in the same order. The three parts are:

[circulation status/][size-][type]

The separation characters are omitted if that section is omitted

Circulation status:
SR	Special Reserve. These books cannot be taken out of the library and can only be read with a keyholder present or with Skinnerial permission.
R	Reserve. These books do not circulate outside the library and cannot be checked out
(none)	Books without a / prefix are available to be checked out by members.

Size:
S	Small books up to 8 inches in height. Generally mass-market paperbacks.
L	Large books up to 11 inches in height. Generally mass-market hardcovers.
VL	Very large books up to 12 inches in height. Often reference or art books.
XL	eXtra large books bigger then 12 inches in height. Coffee table books.
F	Foreign books. These can be S or L. Foreign books larger than that are kept with the English version
(none)	A section of books that can be any size

Type:
(none)	Fiction. This is the default value if only a size is present
A	Anthologies
ART	Art books
ARTIFACT	Weird non-book stuff that doesn't really belong anywhere else
B	Booklets. Small chapbooks, mostly dating from the 50s.
BLB	Big Little Books. Very small (physically) books that were marketed to children.
CAL	Calendars
CX	Comics
DICT	Dictionaries
IND INDF	Indexes (to fandom, etc). INDF is a folder of unbound pages
MM	Multimedia, including cassettes, CDs, DVDs, games, etc.
REF	Reference books
SCRIPT	Scripts
X	Adult. Keep locked away from the kids
V	Valuable. First editions, misprints, very old stuff.
AD BD BS D BS ERD GN GRD GZD MB OVD TD	Doubles. These were popular in the 60s mostly where they stuck two books together by two different authors and you flipped the book over to get the other title. They are a giant pain in the dex and, happily, not really published any more. All the different shelfcodes represent the different publishers of these.
DEU FRA ITA JPN KOR LAT MISC NLD POL POR RUS SPA TLH ZHO	Foreign subcategories. Most of them are obvious what country they are. LAT is Latin. TLH is Klingon. MISC is any language for which we only have one book in that language.