CKEditor - Real-time collaborative future-ready rich text editor
ContentTools - A small & beautiful WYSIWYG editor for HTML content.
TinyMCE - TinyMCE is a content editor that functions as a plug-in for Wordpress websites.
SquareSpace - Squarespace is the easiest way for anyone to create an exceptional website. Pages, galleries, blogs, e-commerce, domains, hosting, analytics, 24/7 support - all included.
Aloha Editor - Aloha Editor is an HTML5 WYSIWYG Editor that gives you a total new experience when editing.
Quill - Powerful, API-driven rich text editor