Reviser is an inline wysiwyg editor, meaning you can edit the node body content without going to the edit page. Just click anywhere on the node body and start editing. Since you are actually editing the HTML DOM on the same page where the content is actually viewed all changes you make will appear exactly the same when you hit save. A true what-you-see-is-what-you-get experience that a wysiwyg editor should provide
This really is finally a wysiwyg editor that you will want to use. There is no need to go between the edit and view pages to make sure everything looks right. Just edit away until it 100% correct, hit save and then you are done.
At the moment this editor does not replace any existing editors on the node create or edit pages it only works inline when viewing a pages that contains node content. There are also some other issues to be resolved like links in the node body are not accessible to users when this editor is enabled.
Development sponsored by univate.
Based on code from twoism