Graphic character identifiers

This document gives information on identifiers assigned to various graphic characters using the IBM graphic character identification system. IBM has an established system to uniquely and uniformly identify and name graphic characters. This system provides for character identification using one of the following graphic character identifiers:

Graphic Character Global Identifier (GCGID).
The GCGID identifies graphic characters defined by IBM. The GCGID definition uniformly associates arbitrary graphic character shape with an eight-character identifier GCGID. It also provides a short description for each GCGID.

Graphic Character UCS Identifier (GCUID).
The GCUID format is for defining additional characters and sets of characters that (mostly) exist in the Universal Coded Character Set (UCS) defined in ISO/IEC 10646 and Unicode standards and need to be used in IBM resource definitions such as IBM code pages. The format allows all current and future characters from UCS planes 0 through 16 to be described. It also allows for identifying characters and glyphs that are not defined in UCS as well as glyph variants of the unified Han area of UCS.

For those characters that exist in the UCS, the standardized graphic character name is used as a description for the GCUID.

Both GCGID and GCUID identifiers are compatible with each other since they share the same basic format and provide identifiers that are globally unique. Unless there is a special need to differentiate between GCGID and GCUID, both may be used interchangeably.

The GCGID and GCUID are identifiers from two different systems to identify individual members of the total collection of all characters. Since the two identifiers can point to the same character, this system also establishes an equivalence for some of them.

In general, only identical characters are listed as equivalent. For example, GCGID LA010000 (a small) is identical to U0000061 (LATIN SMALL LETTER A). This information can be used to generate mapping tables between UCS and individual IBM code pages that may be described using only the GCGIDs. However, it is not always possible to create correct UCS mapping tables by using only the primary equivalences given in this document. In practice, the conversion tables from IBM code pages to UCS may occasionally not map to the character shown in this document as equivalent. There are cases where the character being used in a code page, for historical or other reasons, is a synonym of another character defined in the system. For example, in IBM code page 819 the character at 0xAF is defined as GCGID SM150000, "overline", which has the GCUID of U000203E. However, in the mapping table this character is mapped to U00000AF, which is the "macron", a synonym of "overline", since that is how the character is actually used.

The list of GCGID tables below identifies assigned GCGIDs and GCUIDs by category.

Graphic Character Global Identifier (GCGID) tables