View DDC number information

Elements

Each classification, subject heading or table number represents an entry in the DDC schedules or tables synthesized according to instructions in the schedules and/or tables.
Each record contains a DDC number, a caption (heading) describing the class (subject) that the number represents, a representation of the class number’s position in the DDC hierarchy, and term(s) from the DDC Relative Index.
Records include terminology associated with the number from Library of Congress subject headings.

Element details

Element	Description
DDC Number	See the DDC number types table for details.
Caption	For each DDC number in the schedules, tables, and manual, a caption (heading) defines the subject or subdivision that number represents.
Hierarchy	Each Dewey Linked Data record contains a representation of the number’s position in the DDC hierarchy. Click on the hyperlinked text labels to go to a higher level in the hierarchy
Download	Click Download to the DDC number's information as a .JSON file.
URI	Each DDC number has an associated URI that can be copied or downloaded as a .JSON file.
Entity type	Each DDC number has an associated entity type. For more information, see the WorldCat ontology guidelines and standards.
Notes	Certain notes may be present in the schedules and tables. Scope notes indicate that the meaning of a class number is broader or narrower than is apparent from the heading Revision notes appear in the history box and warn users that there have been changes in the subdivisions of a class since the previous edition and indicate the degree of revision
Terminology Sources Most records for schedule numbers contain terms from the DDC Relative Index and Library of Congress subject headings associated with the class numbers.
Relative Index Terms	Note: You must be signed in to see this information. Terms from the DDC Relative Index name the topics covered by the number in the record. Many Relative Index terms have subheadings (preceded by two hyphens) that indicate the discipline in which the topics are treated in the class represented by the number.
Other numbers	All users can view the first level of narrower classes subordinate to the number in the Narrower box. Users who are signed in can also view related numbers in the Related box.

DDC number types

Number type	Example	Description
Class number	004.67	Number or span of numbers provided in the DDC schedules to represent a subject.
Built class number	B 598.176	A number constructed according to add instructions stated or implied in the schedules or tables to represent a specific subdivision of a DDC class.
Centered entry	C 930-990	Represents a subject covered by a span of numbers.
Optional number	(921)	Number enclosed in parentheses; a class number that is an optional alternative to the number usually assigned to a concept.
Bracketed number	[104] Unassigned 511[.22] Intuitionistic mathematics [291] Comparative religion T5--[04] Persons of mixed ancestry with ethnic origins from more than one continent	Number enclosed in square brackets; a number that has been discontinued or relocated, or an unassigned number. Record instructs you not to use this number and provides a cross-reference to the correct class number.
Table number	T1--071	Number for an entry in one of the DDC numbered auxiliary tables (Tables 1–6; in the Abridged Edition, Tables 1–4). Provides notation that can be added to other numbers to make a class number appropriately specific to the work being classified.
Built table number	T4--092	A number constructed according to add instructions stated or implied in the schedules or tables to represent a specific subdivision of a DDC table.
Table centered entry	T2--4- T2--9	Number used to indicate and relate structurally a span of table numbers that together form a single concept.
Add table notation	617:028	Number for an entry in one of the DDC add tables (lists of special notation found in add notes under specific numbers throughout the schedules and occasionally in Tables 1–6). What precedes colon is class number or span where add table is located; what follows colon is notation to be added. Provides notation that can be added to other numbers, as instructed at the beginning of the add table, to make a class number appropriately specific to the work being classified.
Manual number	M 361-365	A number or range of numbers covered in an entry in the DDC Manual. The manual entry explains the proper use of the class number (or range).