In WordPress, the visual editor used to edit the content in posts and pages is a WYSIWYG editor. Instead of editing the content using HTML code, you can just select a couple of words, click the “Bold” button, and immediately see how it will look when the content is published. It makes it a lot easier to get a sense of the end result, and saves you the trouble of clicking the “Preview Changes” button every time you want to check your work.
Another part of the WordPress administration panel that operates by the WYSIWYG paradigm is the customizer. In the customizer, you can change menus, widgets, colors, logos, header images and titles, and immediately see the end result reflected in the preview window.