The first edition of the euro is under ultraviolet light, and the front of the euro paper money is purple, printed with the European Union flag and the signature of the president of the European Central Bank.
The flag of the European Union is blue with 12 yellow stars, which represents the United and harmonious atmosphere that European countries will show when they get together, and the theme pattern symbolizing the interweaving of blue and yellow becomes the eternal image symbol of the unified currency of the whole euro zone.