Chapter 26 Numerically Systems*

decimal numeric filing

Developed primarily for library use in the late 1800s, the decimal system is based on 10 general categories (e.g., 500 Pure Science). The major numeric groupings are each further divided into 10 parts (540 Chemistry), which are then subdivided into 10 subunits (540.1 Philosophy and Theory).

straight-numeric filing

a system in which files are arranged consecutively in ascending order, from the lowest number to the highest.

Chronological filing

a type of numeric arrangement, which uses numeric dates as the indexing units. The most common order of units is year, month, and day, as in 89-12-06 to denote the sixth of December, 1989.

Terminal-digit numeric filing

the last digit is the primary unit used for filing; the units are filed in order by the last digits, middle digits, and then the first digits in the number. e.g., 24-68-10); Primary Unit (10), Secondary Unit (68), and Final Unit (10).

middle-digit filing

the middle digit of each number becomes the primary indexing unit. The units are filed in order first by the middle digits; next, according to the digits on the extreme left side; and last, according to the digits on the extreme right side of the number

duplex-numeric system

uses two or more sets of code numbers for records, with the sets separated by dashes, commas, periods, or spaces. Records are filed consecutively by the primary number and then sequentially by the second number, and so on.