ISO/IEC 8859-15:1999, , is part of the ISO/IEC 8859 series of ASCII-based standard character encodings, first edition published in 1999. It is informally referred to as Latin-9 (and for a while Latin-0). It is similar to ISO 8859-1, and thus also intended for “Western European” languages, but replaces some less common symbols with the euro sign and some letters that were deemed necessary:Information technology — 8-bit single-byte coded graphic character sets — Part 15: Latin alphabet No. 9
A proposal called ISO 8859-0 was made in 1997, to replace 4 unused or rarely used ISO 8859-1 characters (¤, ¨, ´, and ¸) with €, Œ, œ, and Ÿ. € became necessary when the euro was introduced. Œ and œ are French ligatures, and Ÿ is needed so that French text can be converted from lower-case to all-caps and back again without loss. Ironically, the last three had already been present in DEC's Multinational Character Set (MCS) in 1983, a character set from which ECMA-94 (1985) and ISO-8859-1 (1987) were derived. Since their original codepoints were now occupied by other characters, less logical codepoints had to be chosen for their reintroduction.
The same proposal also recommended replacing 6 more characters (¢, ¦, ±, ¼, ½, ¾) with "some other characters to cover a maximum of languages".  For the euro sign, some wanted to replace the plus-minus sign instead of the currency sign. The currency sign is used in some applications as a field separator and in some others to indicate subtotal). There was strong opposition to this. One person said "The proposed «+-» is not an adequate fall-back, as this sequence, though rarely used, has already a fixed mathematical meaning, quite different from «±»; and, even if a reader would deduce the intended meaning, «±», from the context, «+-» in lieu of «±» will hurt a physicist's æsthetic feelings at least as much as «oe» in lieu of an o-e ligature a Francophone's.."  In the end the ± and ¢ were not replaced. Eventually four characters were selected: Š, š, Ž, and ž, which are used in Finnish and Estonian for the transliteration of Russian loanwords and names. The proposal was renamed to ISO 8859-15.[when?]
There were attempts to make ISO 8859-15 the default character set for 8-bit communication, but it was never able to supplant the popular ISO 8859-1. It did see some use as the default character set for the text console and terminal programs under Linux when the euro sign was needed, but the use of full Unicode was not practical, but this has since been replaced with UTF-8.
ISO 8859-15 encodes what it refers to as "Latin alphabet no. 9". This character set is used throughout the Americas, Western Europe, Oceania, and much of Africa. It is also commonly used in most standard romanizations of East-Asian languages.
Each character is encoded as a single eight-bit code value. These code values can be used in almost any data interchange system to communicate in the following languages:
For some languages listed above, the correct typographical quotation marks are missing, since only «, », ", and ' are included.
Also, this encoding does not provide the correct character for the apostrophe, and oriented single high quotation marks, although some texts use the spacing grave accent and spacing acute accent, which are both part of ISO 8859-1, instead of the 6-shaped/9-shaped quotations marks or apostrophes (and this works reliably with some font styles, where all these characters are displayed as slanted wedge glyphs).