LibAnswers: Library answers

A classmark is a set of letters (and sometimes numbers) assigned to books and other library material so they are arranged by subject on the shelves.

The classmark tells you the exact shelf location for a particular item, eg TDG (H).The main part is a set of letters representing the subject of the item. The letter in brackets after the classmark is usually the first letter of the author's surname (or sometimes the title) and is used to shelve books which have the same classmark in a logical order.

Each subject has its own letter. The subjects are then subdivided, eg:

As well as capital letters we also use numbers, stops and lower case letters for different aspects of the subject. Lower case letters indicate a geographical region. On the shelves it would look like this: