Call numbers in a formal arrangement are mechanical and
unrelated to a book’s content. Their purpose is merely for the
storing and accurate locating of books. The order of books on
shelves in these libraries does not make sense to users. A call
number in a systematic arrangement, however, holds information
about the book’s content; it can reveal the author and often
indicates the title. As books using this method are grouped by
subject, this arrangement is relevant whenever there is a need to
support subject shelf browsing. Hence, this explicit and contentrevealing
type of call number used to be termed signatura loquens
(Lat. ‘speaking’ call number) - as opposed to a call number using
a mechanical and meaningless accession number which is
described as signatura mystica (Lat. secretive call number).
The link between call numbers and classification,