Bidirectional text embedding and override


The Martian presents,

Bidirectional text embedding and override


Howdy Earthlings!

“-----“ here again!  *sigh* Yeah, some of you Earth people still confuse me with being Martian.  For the record AGAIN, I come from the planet “-----“ (sorry, our names just don’t translate to English or any other earthly language)  Now, I have joined with the Office Global Experience team, because people on your planet need to know how to take advantage of the great global features that Office has to offer.


I know, it has only been two short weeks on Earth, since I last shared my wisdom with you in my post of ‘What happens when the same font is used to display multi-language text?’.  But, do you know how many years have gone by on some other planet, in some other Galaxy far far away?!  No time to be wasted, besides, we “------“ians just have so much brain power to share.  If I don’t offload my knowledge frequently enough, it could literally overflow my neural system. (A few seconds for you to grasp this…)  Alright, I am being a bit dramatic here.  I am just too excited to share with you the technical insights of Office 2010.  Let me walk fly you through how Office handles bidirectional text embedding and override.  Don’t worry, if you have no clue what this means right now, I’ll be able to wirelessly beam the concept into your brain.  Fasten your seatbelt. Houston, we are ready to take off…


Microsoft is a leader in the software industry when it comes to offering comprehensive bidirectional text support for its products. Today, with every new feature that they add to Microsoft Office applications, we continue to ensure that Bidirectional support is built into the feature at design time. In addition, we continue to look for opportunities to further enhance this support to meet customers’ needs. If you are a Microsoft Word user who often creates and edits text in a right-to-left language (like Arabic or Hebrew), you’re probably aware of the explicit directional tagging of text; this is where applications rely on the language of the keyboard to determine the direction of the text. This design provides users a simple method to control the layout of neutral characters (such as SPACE) and numbers regardless of the surrounding characters.

In Word 2010 we added two new features that will extend this control of Bidirectional text. Are you ready to super activate your brain for these exciting new advanced features called Bidirectional Text Embedding and Bidirectional Text Override? 

Bidirectional Text Embedding


Embedding is an advanced feature specified in the Unicode Bidirectional Algorithm. This feature solves the problem of trying to insert a sentence into a paragraph with a different directionality. For example, inserting an English quote in the middle of a right-to-left paragraph. 

For clarity, in the examples below lower case represents English text characters and UPPER CASE represents right-to-left characters.

Assume that you would like to write the following line in a left-to-right paragraph according to the keyboard input sequence:

clip_image002 = he said “I WILL CALL sandy TODAY”

If you try to write this sentence today without the help of embedding, the text will display as follows:

  clip_image004  he said “LLAC LLIW I sandy YADOT”

        ?------? ?---------? ?---? ?----?

           1          2        3      4

What you really would like to see is the following:

  clip_image004  he said “YADOT sandy LLAC LLIW I”

        ?------? ?---? ?---? ?---------?

           1       4     3        2

Using Office 2010, this can easily be done by inserting two special hidden control characters before and after the sentence you would like to embed. In the example above it would be the quote. These control characters are the “Right-to-Left Embedding” (RLE) character at the beginning of the quote and the “Pop Directional Formatting” (PDF) character at the end of the quote. Your keyboard input text will be:

clip_image006 = he said [RLE]“I WILL CALL sandy TODAY”[PDF]

*To insert these special characters, please refer to the instructions at the end of this document.

Bidirectional Text Override


Override is another advanced feature that is specified in the Unicode Bidirectional Algorithm. This feature allows users to force the layout of a group of characters to a specific direction regardless of their classification. For example, you want to write a part number and you want to ensure that all the characters flow left-to-right. This number could consist of numerals and right-to-left characters. Without using the overrides, the right-to-left letters will flow right-to-left, while the numbers will flow left-to-right and both will influence the layout of the surrounding text.

For clarity, in the examples below lower case represents English text characters and Upper case for right-to-left characters.

For example, you want to write the following sentence according to the keyboard input sequence in a right-to-left paragraph:

clip_image008 = PRODUCT NUMBER IS ABC632XPS

Without the override feature, the display will be as follows:

        clip_image009 SPX632CBA SI REBMUN TCUDORP


        3  2          1

What you would like to see is:

      clip_image010 ABC632XPS SI REBMUN TCUDORP

       ?-------?    ?---------------?

           2             1

Using Word 2010, this can easily be done by inserting two special hidden control characters before and after the part number. In the example above, you need to precede the part number with the “Left-to-Right Override” (LRO) control character and the “Pop Directional Formatting” (PDF) character at the end of the part number. Your input text will be:


*To insert these special characters, please refer to the instructions below.


Inserting Unicode Special Characters

There are two easy ways to insert special characters in Word 2010.  And, when I say “easy”, I actually meant EASY.  We “------“ians are just that straight forward!  Isn’t that nice?


#1. Using the Ribbon

  1. Position your cursor at the desired insertion point in your document.

  2. Click the Insert tab.

  3. In the Symbol ribbon, click on the Symbol icon.

  4. From the drop down menu, choose “More Symbols…” This will open the Symbol dialog box.

  5. Switch to the “Special Characters” tab.

  6. Scroll down to the end of the list.

  7. Select the special character you want to insert and click Insert.

  8. When you have inserted the character or characters you need, click the Close button to close the dialog.


Insert Special Characters Using the Ribbon

#2. Using the Keyboard

  1. Position your cursor at the desired insertion point in your document.

  2. Type the Unicode hexadecimal code for your character (using the table below). For example type “202B” for RLE.

  3. Press ALT+X.

  4. The character code numbers will disappear and they will be replaced with the equivalent hidden special character.


Control character name

Unicode abbreviation

Character code


















You can use the method above to insert any Unicode character using its code. You can also do the opposite. Position the cursor after any character in your document and press ALT+X to display its Unicode code.


Well I hope you enjoyed our journey into the Bidirectional text world, and that your brain neurons are firing at full blast…. … …


I would have talked to you about these features in binary, but thanks to Ayman Aldahleh for helping me to translate it into English! He is truly a multi-lingual Earthling!  Ayman is the Development Manager of the Office Global Experience Platform (GXP) team at Microsoft. His team specifically focuses on making sure the Office applications are ‘world-ready’! Ayman is originally from Palestine, but he and his team work in Redmond, Washington, USA, The Earth, The Solar System, The Milky Way Galaxy, The Universe.  He has been working at Microsoft since 1991.  Prior to GXP, Ayman had lead and worked in the development teams that enabled several Microsoft products in multiple languages including complex scripts.  In his spare time, he enjoys parenting, photography, travel, cooking and various outdoor activities.

Assisting Ayman with this article were Ziad Khalidi, Gwyneth Marshall and Murtuza Shakir.

The example companies, organizations, products, domain names, email addresses, logos, people and events depicted herein are fictitious. No association with any real company, organization, product, domain name, e-mail address, logo, person, or event is intended or should be inferred.

Comments (7)
  1. Anonymous says:

    Thanks for the interesting blog..

    It will help me a lot if I could use these features inside equations. My work sometimes requires me to write Arabic text inside equations, but the program reverses the equation text, so I have to write it in the opposite order to get the right appearance.

    When I tried to use the features you discussed, Word displayed the message "Math zones can’t include bidirectional override or bidirectional embedding characters".

    Can you help me solve this problem?

    Thanks in advance

  2. Anonymous says:

    Unfortunately, the equations feature in Office only supports left to right layout and text rendering.  

  3. Naftali says:

    Thank you for this informative page. But I cannot get it to work. I am trying to type Hebrew text with occasional words in English in the middle. So when I put the cursor where the English text should go, and try to type 202A, first of all the A comes out as a Hebrew letter (naturally, since I am in Hebrew mode). So I change to English mode – then the 202A comes out on the right hand end of the line I am typing.  When I press ALT X  it gives me some numbers (presumably code) on the right hand end of the line.  Writing in English then just comes out at the same place, on the right hand end of the line, instead of somewhere in the middle..Any advice please?

  4. Naftali says:

    In addition, the same thing happens when I use the Insert – symbol -special symbol route. Inserting the left to right mark or left to right embedding makes the cursor jump to the right hand end of the line.

  5. Josef says:

    Does Word 2013 has this feature embadedly? When I click the icon on the menu bar (Right to left) / icon (Left to right) does it apply the control characters (RLE, LRE … ) ? or how does it work ?

  6. THE ONE says:

    Thanks, I got much….

Comments are closed.

Skip to main content