What is "code point"

n. (context computing English) A numerical offset in a character set, etc., as opposed to the character or item it represents.

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 to 7F, Extended ASCII comprises 256 code points in the range 0 to FF, and Unicode comprises 1,114,112 code points in the range 0 to 10FFFF. The Unicode code space is divided into seventeen planes (the basic multilingual plane, and 16 supplementary planes), each with 65,536 (= 2) code points. Thus the total size of the Unicode code space is 17 × 65,536 = 1,114,112.