Layout (bidirectional text and character shaping) overview

Edit online

Bidirectional (BIDI) text results when texts of different direction orientation appear together. For example, English text is read from left to right. Arabic and Hebrew texts are read from right to left. If both English and Hebrew texts appear on the same line, the text is bidirectional.

For further information about directional text and character shaping, including a list of available publications, see the following web address:

http://www.opengroup.org
Write bidirectional text according to the following guidelines:
  • Arabic and Hebrew words are written from right to left. (A character string is considered a word for the purposes of sequencing in an alphanumeric environment.)
  • Numbers and English quotations are written from left to right.
  • Digits and their punctuation marks are written from left to right.

Bidirectional script is read from right to left and from top to bottom.

If the embedded text is contained in one line, the text is written from left to right and embedded in the bidirectional text. However, if the embedded text is split between two or more lines, the correct order must be maintained in the left-to-right portions to allow top-to-bottom reading.

For example, right-to-left text embedded in left-to-right text that is contained in one line is written as follows:

THERE IS txet lanoitceridib deddebme IN THIS SENTENCE.

Right-to-left text embedded in left-to-right text that is split between two lines is written as follows:

THERE IS senil owt neewteb tilps si taht txet lanoitceridib deddebme IN THIS SENTENCE.

Both texts maintain readability even though the embedded text is split.