WYSIWYG stands for "What You See is What You Get". Basically, it works much like Microsoft Word or similar word processing software. It is very useful in helping people manage, edit, and update the pages of their website quickly by seeing the changes instantly right on their monitors.
You can see on the screen how the page will look when you are finished. You can add text, images, documents, and hyperlinks. You can add styles to the font and change how the text will look by adding inline styles right to your content.