Design Feed

The Design Feed palette provides a way of adding messages and images to a
drawing, which you can then share with colleagues, clients, and consultants
online through Autodesk 360. 

AutoCAD 2015 enables you to store them locally on your computer’s hard
drive. 
In this case, the Design Feed data for these drawings are still stored
in Autodesk 360
But the association to the Design Feed data is maintained by a unique Design Feed ID, which is saved in the drawing.