Distraction free writing mode is designed to keep your writing area clean and save you from possible distractions when writing new articles.
A click on TinyMCE distraction free writing more button on visual editor simply hides everything that can get in the way of your writing, thus helps you to stay focused.
WordPress 4.1 is here, the update is mainly focused on your writing, flawless language support, new default theme and an instant access to distraction free writing mode.
Before clicking distraction free writing mode button:
After clicking distraction free writing mode button:
The update on distraction free writing mode is just awesome, it doesn’t takes you on full screen but instantly creates a full screen by hiding the left admin sidebar, top admin bar and the right side metaboxes also goes invisible.