What You See Is What You Get... WYSIWYG
It's a type of HTML editor that lets you make web pages without requiring HTML coding. Instead you simply insert pictures, text, links, and colors. It is a good idea to always use the same web editor program in which a site was originally created, as using a very different program can potentially corrupt the original design.
Both site builders we provide use WYSIWYG, as well as the HTML Editor that you can find in cPanel > File Manager.
Additionally, WordPress (which can be installed from our QuickInstall in cPanel) also has the ability to add posts and pages using WYSIWYG.
There are also many third-party HTML Editors available that use WYSIWYG.