Horizontal and vertical writing in East Asian scripts

Many East Asian scripts can be written horizontally or vertically. Chinese, Vietnamese Hán Nôm, Korean, and Japanese scripts can be oriented along either axis, as they consist mainly of disconnected logographic or syllabic units, each occupying a square block of space, thus allowing for flexibility for which direction texts can be written, be it horizontally from left-to-right, horizontally from right-to-left, vertically from top-to-bottom, and even vertically from bottom-to-top.

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Traditionally, Chinese, Vietnamese, Korean, and Japanese are written vertically in columns going from top to bottom and ordered from right to left, with each new column starting to the left of the preceding one. The stroke order and stroke direction of Chinese characters (hanzi in Chinese, chữ Hán in Vietnamese, Hanja in Korean, and kanji in Japanese), Vietnamese chữ Nôm, Korean Hangul, and Japanese kana all facilitate writing in this manner. In addition, writing in vertical columns from right to left facilitated writing with a brush in the right hand while continually unrolling the sheet of paper or scroll with the left. Since the nineteenth century, it has become increasingly common for these languages to be written horizontally, from left to right, with successive rows going from top to bottom, under the influence of European languages such as English, although vertical writing is still frequently used in Hong Kong, Japan, Korea, Macau, and Taiwan.