Code Page - Criticism

Criticism

Many older character encodings, except Unicode, suffer from several problems.

1. Some code page vendors insufficiently document the meaning of all code point values. This decreases the reliability of handling textual data through various computer systems consistently.
2. Some vendors add proprietary extensions to some code pages to add or change certain code point values. For example, byte \x5C in Shift JIS can represent either a back slash or a yen currency symbol depending on the platform.
3. In order to support several languages in a program that does not use Unicode, the code page used for each string/document needs to be stored.

Due to Unicode's extensive documentation, vast repertoire of characters and stability policy of characters, these problems are rarely a concern for Unicode.

Applications may also mislabel text in Windows-1252 as ISO-8859-1. Fortunately, the only difference between these code pages is that the code point values used by ISO-8859-1 for control characters are instead used as additional printable characters in Windows-1252. Since control characters have no function in HTML, web browsers tend to use Windows-1252 rather than ISO-8859-1.