Shift_JIS is a character encoding for Japanese text, established in 1982. It was widely used in Windows systems and older websites in Japan.

In Shift_JIS, ASCII characters use 1 byte and Japanese characters (hiragana, katakana, kanji) use 2 bytes. This is more byte-efficient than UTF-8's 3 bytes for Japanese, but Shift_JIS supports far fewer characters. Character encoding history books explain the origins of Shift_JIS.

While UTF-8 has become the standard, Shift_JIS is still encountered in CSV file imports and legacy system integrations.

Converting between Shift_JIS and UTF-8 can cause mojibake (garbled text), especially with characters like the wave dash (〜) and full-width minus (−). Legacy system migration guides cover encoding conversion challenges.