As is normally said, an image paints a thousand words, and this is the philosophy of Disk Space Finder. It tells you visually of the space in your partitions, both occupied and free.
Thus, with a quick glance you can see which are the largest folders, verify if they are needed, or if you prefer delete them easily. That way you can free up some more space on your hard drive.
To work correctly you need to previously install NET Framework 3.0 or later.