What is the Rich Text Editor?
In most areas of the system where text can be entered, you can control the appearance of your text using the Rich Text Editor, sometimes called a WYSIWYG (What You See Is What You Get) editor. The rich text toolbar has icons for editing and formatting your text. You may use the rich text editor to include images, links, audio, and video as well as text.
The Rich Text Editor is based on an open-source application called CKEditor. For more information on the CKEditor, you may also refer to the CKEditor 4 Documentation Site.
Important: To avoid losing your work, we recommend that you first compose and save it elsewhere (e.g., in MS Word, Google Docs, etc.) Then paste your text into the rich-text editor, and format it as needed. Also, by default, an auto-save feature is enabled to allow the browser you’re using to store for a limited time the rich-text content you’re entering into the editor so that it can be retrieved if you accidentally navigate away from the Sakai page in which you are working. For more details about this feature, see the article How does auto-save for the Rich-Text Editor work?
Rich Text Editor Toolbar

The Rich Text Editor toolbar contains an array of icons. See What actions can I perform using the Rich Text Editor icons? for more information on individual icon functionality.