CKEditor is a text editor to be used inside web pages. It's a WYSIWYG editor, which means that the text being edited on it looks as similar as possible to the results users have when publishing it. It brings to the web common editing features found on desktop editing applications like Microsoft Word and OpenOffice.

Because CKEditor is licensed under flexible Open Source and commercial licenses, you'll be able to integrate and use it inside any kind of application. This is the ideal editor for developers indented to provide easy and powerful solutions to their users.
CKEditor vs. Word

CKEditor is not a desktop application like Microsoft Word or OpenOffice. It's a component to be used by developers to enhance their applications. It's an editor to be used inside web pages.
CKEditor and FCKeditor

FCKeditor has been around for more than six years. Since 2003 it has built a strong user community becoming the most used editor in the market, accumulating more than 3,5 million downloads. On 2009, we decided renaming the editor, bringing to the light our next generation solution: CKEditor 3.0.

CKEditor inherits the quality and strong features people were used to find in FCKeditor, in a much more modern product, added by dozens of new benefits, like accessibility and ultimate performance.