About this character
The euro sign was designed by a small European Commission team that included the German graphic designer Arthur Eisenmenger, who later said he had sketched the form decades before the euro became a unit of account. The final design — a Greek epsilon with two horizontal bars, inspired by the C of Carolus and the E of Europa — was unveiled by the Commission on 12 December 1996. The two bars were intended to convey stability, and the official 1997 specification ("Style Guide for the use of the euro sign") prescribed exact geometric proportions for institutional use.
U+20AC was added to Unicode 2.1 in May 1998, in time for the introduction of the euro as a unit of account on 1 January 1999. This was the first time the Unicode Consortium had made an unscheduled mid-version addition: the major release schedule of Unicode 2.0 (1996) had passed and Unicode 3.0 was not due until 1999, so 2.1 was created specifically to deliver the euro sign and a small number of corrections. The decision had downstream effects: software vendors who had built character tables on 2.0 had to retrofit support, and Windows-1252 (Microsoft's superset of Latin-1) repurposed the unused 0x80 slot for the euro, a workaround whose legacy still occasionally produces mojibake when documents are misidentified as ISO 8859-1.
The euro sign has Bidi class ET (European Terminator), the same as U+00B0 ° DEGREE and other unit indicators: in bidirectional contexts it attaches to a preceding number. House styles disagree on whether the sign precedes or follows the amount and on whether to use a space — English-language usage typically writes €10, French 10 €, German 10 € with a non-breaking space. The Unicode standard does not encode any of these conventions; they are typesetting choices. Companion currency-sign codepoints in the same block include U+20A4 ₤ LIRA SIGN, U+20A9 ₩ WON SIGN, U+20B1 ₱ PESO SIGN, and U+20B9 ₹ INDIAN RUPEE SIGN.
From the Unicode data
Its East Asian Width is Ambiguous: it takes one column in Western contexts and two in East Asian legacy contexts, a common cause of misaligned tables in terminals.