Yen and yuan sign

The yen and yuan sign (¥) is a currency sign used for the Japanese yen and the Chinese yuan currencies when writing in Latin scripts. This character resembles a capital letter Y with a single or double horizontal stroke. The symbol is usually placed before the value it represents, for example: ¥50, or JP¥50 and CN¥50 when disambiguation is needed. When writing in Japanese and Chinese, the Japanese kanji and Chinese character is written following the amount, for example ５０円 in Japan, and ５０元 or ５０圆 in China.

Japan
After the institution of Japan's New Currency Act, from 1871 through the early 20th century, the yen was either referred to (in documents printed in Latin script) by its full name yen, or abbreviated with a capital "Y". One of the earliest uses of ¥ can be found in J. Twizell Wawn's "Japanese Municipal Government With an Account of the Administration of the City of Kobe", published in 1899. Usage of the sign increased in the early 20th century, primarily in Western English-speaking countries, but has become commonly used in Japan as well.

Code points
The Unicode code point is. Additionally, there is a full width character, ￥, at code point for use with wide fonts, especially East Asian fonts.

There was no code-point for any ¥ symbol in the original (7-bit) US-ASCII and consequently many early systems reassigned 5C (allocated to the backslash (\) in ASCII) to the yen sign. With the arrival of 8-bit encoding, the ISO/IEC 8859-1 ("ISO Latin 1") character set assigned code point A5 to the ¥ in 1985; Unicode continues this encoding.

In JIS X 0201, of which Shift JIS is an extension, assigns code point 0x5C to the Latin-script yen sign: as noted above, this is the code used for the backslash in ASCII and also subsequently in Unicode. The JIS X 0201 standard was widely adopted in Japan.

Microsoft Windows
Microsoft adopted the ISO code A5 in Windows-1252 for the Americas and Western Europe but Japanese-language locales of Microsoft operating systems use the code page 932 character encoding, which is a variant of Shift JIS. Hence, 0x5C is displayed as a yen sign in Japanese-locale fonts on Windows. It is thus displayed wherever a backslash is used, such as the directory separator character (for example, in C:¥ rather than C:\) and as the general escape character (¥n). It is mapped onto the Unicode (i.e. backslash), while Unicode  is given a one-way "best fit" mapping to 0x5C in code page 932, and 0x5C is displayed as a backslash in Microsoft's documentation for code page 932, essentially making it a backslash given the appearance of a yen sign by localized fonts. (Similarly in Korean versions of Windows, 0x5C was reassigned to hold the Won sign (₩) and has similar presentation issues.)

Mac OS
The symbol "¥" can be generated on most non-JP Mac OS keyboard layouts which do not have a dedicated key for it, typically through:

IBM EBCDIC
IBM's Code page 437 used code point 9D for the ¥ and this encoding was also used by several other computer systems. The ¥ is assigned code point B2 in EBCDIC 500 and many other EBCDIC code pages.

Chinese input methods
Under Chinese Pinyin input method editors (IMEs) such as those from Microsoft or Sogou.com, typing displays the full-width character ￥, which is different from half-width ¥ used in Japanese IMEs.

Native characters
The Japanese kanji 円 (yen), and Chinese character 元 and 圆 (yuan) are used when writing in Japanese and Chinese. In Hong Kong, Taiwan, Macau and Singapore, although the currency is written with a dollar sign ($) (or HK$, NT$, MOP$ or S$ when necessary to indicate which dollar is meant) in Latin script, it is also rendered as 元 and 圓/圆 (yuan) when writing in Chinese. The name of the North Korean and South Korean won (₩) comes from the equivalent hanja 圓 (원, won).

Turkmenistan
In the 1993 Turkmen orthography, the Yen sign was used as the capital form of ÿ and represented the sound. It was replaced with Ý in 1999.