PATH Mac OS 8 and 9 Developer Documentation > Text and Other International Services > Text Encoding Conversion Manager
Programming With the Text Encoding Conversion Manager

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ISO/IEC 10646

The ISO/IEC 10646 standard defines two alternative forms of encoding:

• a 32-bit encoding, which is the canonical form. The 32-bit form is referred to as UCS-4 (Universal Character Set containing 4 bytes)

• a 16-bit form that is referred to as UCS-2

The ISO/IEC 10646 nomenclature refers to coded characters as multiples of octets, while the Unicode nomenclature refers to coded characters as indivisible 16-bit entities. The Unicode standard does not include the UCS-4 format.