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DDC number

Find the DDC number types WebDewey provides records for, including examples and descriptions.

WebDewey provides records for the following types of DDC numbers.

Number type Example Descripción
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 tables. 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. ADD IMAGE
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.
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). ADD IMAGE