Bi-directional Text

Bi-directional text is text containing text in both text directionalities, both right-to-left (RTL) and left-to-right (LTR). It generally involves text containing different types of alphabets, but may also refer to boustrophedon, which is changing text directionality in each row.

Some writing systems of the world, notably the Arabic and Hebrew scripts, and derived systems such as the Urdu, Persian, Yiddish, Jawi, and Ladino scripts, are written in a form known as right-to-left (RTL), in which writing begins at the right-hand side of a page and concludes at the left-hand side. This is different from the left-to-right (LTR) direction used by most languages in the world. When LTR text is mixed with RTL in the same paragraph, each type of text is written in its own direction, which is known as bi-directional text. This can get rather complex when multiple levels of quotation are used.

Many computer programs fail to display bi-directional text correctly. For example, the Hebrew name Sarah (שרה) is spelled sin (ש) resh (ר) heh (ה) from right to left. Note: Some web browsers may display the Hebrew text in this article in the opposite direction.