Code point

In character encoding terminology, a code point or code position is any of the numerical values that make up the code space. Many code points represent single characters but they can also have other meanings, such as for formatting.

For example, the character encoding scheme ASCII comprises 128 code points in the range 0_hex to 7F_hex, Extended ASCII comprises 256 code points in the range 0_hex to FF_hex, and Unicode comprises 1,114,112 code points in the range 0_hex to 10FFFF_hex. The Unicode code space is divided into seventeen planes (the basic multilingual plane, and 16 supplementary planes), each with 65,536 (= 2¹⁶) code points. Thus the total size of the Unicode code space is 17 × 65,536 = 1,114,112.

Definition

The notion of a code point is used for abstraction, to distinguish both:

This is because one may wish to make these distinctions: