ISO8859

ISO/IEC 8859, often written ISO-8859 or ISO8859, is a family of eight-bit single-byte character encodings designed to represent text in various languages. Each part of the standard defines a distinct encoding. In all parts, the lower half of the byte (0x00–0x7F) is identical to ASCII, while the upper half (0xA0–0xFF) is allocated to language-specific characters. The range 0x80–0x9F is reserved for control codes in ISO-8859.

The family covers a range of linguistic sets. ISO-8859-1 (Latin-1) targets Western European languages. ISO-8859-2 (Latin-2) covers Central and Eastern European languages. ISO-8859-5 encodes Cyrillic, ISO-8859-6 Arabic, ISO-8859-7 Greek, and ISO-8859-8 Hebrew. ISO-8859-9 (Latin-5) provides Turkish characters, while ISO-8859-15 (Latin-9) updates Latin-1 by adding the euro sign and other characters omitted in Latin-1.

History and usage: ISO/IEC 8859 was developed to provide standardized single-byte encodings before Unicode became widespread. Although Unicode and its UTF-8 encoding now dominate text interchange, ISO-8859 encodings persist in legacy data, older systems, and some email and file formats. They are frequently contrasted with Windows-1252, a Windows encoding that shares many Latin-1 byte values but defines additional printable characters for 0x80–0x9F, leading to potential interoperability issues.

See also: The ISO-8859 family complements other legacy encodings and sits alongside newer universal encodings such as Unicode, which aims to cover all writing systems with a single, extensible standard.