Have you ever ended up with two drawings of the same name, just different time stamps on the file or an added suffix on the file name? Perhaps another team member was trying to be helpful (or not) and edited the file, now you need to know what changed.
Lucky for you there is an Autodesk App for that, and FREE.
After setting the original source drawing and the second version you select the little green arrow in the top of the DWG Compare plugin palette.
Now the results will be listed on the palette and you can select them and it will highlight that specific change. You can see what has been added, modified, or deleted as they are colored green, yellow and red and to make it obvious the non-altered objects are changed to a grey.