Vertical writing
Many East Asian scripts can be written horizontally or vertically. The Chinese, Japanese and Korean scripts can be oriented in either direction, as they consist mainly of disconnected syllabic units and/or ideographic 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. On the other hand, the traditional Kapampangan script, Mongolian script and its offshoots (like Manchu) are written vertically from top-to-bottom.
Horizontal writing is known in Chinese as hengpai (simplified Chinese: 横排; traditional Chinese: 橫排; pinyin: héngpái; literally: "horizontal alignment"), in Japanese as yokogaki (横書き, "horizontal writing", also yokogumi, 横組み), and in Korean as garosseugi (가로쓰기) or hoengseo (횡서; 橫書).
Vertical writing is known respectively as zongpai (simplified Chinese: 纵排; traditional Chinese: 縱排; pinyin: zōngpái; literally: "vertical alignment"), tategaki (縦書き, "vertical writing", also tategumi, 縦組み), or serosseugi (세로쓰기) or jongseo (종서; 縱書).
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Wikipedia