TinyMCE

TinyMce is an awesome Wysiwyg editor. I decided to use TinyMce in my own apps for years now, doesn't matter if i write a blog or cms, newletter tool or webmail, it fits all my needs. Its very easy to install and implement into any web applications within minutes. Customization is easy regarding the very well written documentations.
Tons of Plugins are available for TinyMce, e.g. image managers, filemanagers and so on. You can change its behaviour from a smart and easy Wysiwyg editor with only supporting a few html tags, or enhance it and run an office like textarea :)
Great! I really love it.

all very easy and clear, 5 points

easy setup, use the recently

there is nothing better