bdo element is used to “override the Unicode
bidirectional algorithm”, which in layman’s terms means reversing the
direction of text enclosed between the opening
</bdo> tags. It will often be used with the
xml:lang attributes, given that
a common application of this element is to indicate a change of language
from the rest of the document.
Here’s an example in which the word “Canoe” is reversed:
<p>A palindrome is a word, like 'kayak,' that appears exactly the same when all the letters are reversed. <bdo dir="rtl">Canoe</bdo>, it seems, is not a palindrome.</p>
Use This For …
This element may be used to embed in a page some text that’s in a language that differs from the bulk of the document (for example, embedding a phrase in Hebrew inside a paragraph of English); it may also be used for purely aesthetic reasons.
With the exception of Safari 1.3 and 2, all browsers reverse the text properly.