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When writing articles in Joomla 2.5, you can use either the WYSIWYG editor or you can edit the HTML of the article directly. The HTML editor allows you to view all of the HTML code that makes up an article, where as the WYSIWYG editor hides this code and in essence allows you to preview the article before publishing it.
The WYSIWYG editor also makes it easier to insert special characters into your articles, such as the copyright character. While the HTML editor is generally used by advanced users when working with articles, those same advanced users use the WYSIWYG editor just as often (if not more).
How to toggle between the HTML editor and the WYSIWYG editor in Joomla 2.5
- Begin writing a new article or open for edit any article
- Under the article editor, click the button labeled Toggle editor.
If you in the WYSIWYG mode you will see the HTML view appear, and vice versa.
WYSIWYG Mode HTML editor 
Have you ever tried to edit an article only to find out it was locked? Now that you know how to switch editors, you may want to read our previous article to learn more about locked articles in Joomla 2.5.
