Normal keyboard and mouse copy-and-paste functions will work with CKEditor, but be aware that a special filtering system is applied to all text pasted into the CKEditor window (including text copyed from CKEditor itself). This filtering is designed to remove all of the unnecessary formatting that tends to come from word processors like Microsoft Word, allowing the content to work optimally in the website environment.

Because of this, it is not a good idea to develop content in Word and then try to copy it into your website. At the least, you should avoid doing any kind of layout or detailed formatting of your content while in Word, since a lot of that will be lost when you copy and paste. Focus on just the text itself while in Word, and then later add organization and formatting once the content has been placed into your website.