The freeware Disk Defrag download tidies up your hard drive and speeds up system performance.
Over time, a lot of junk and files accumulate to cause clutter on your hard drive, but you can put an end to them. Disk Defrag tidies up your hard drive and therefore speeds up the system performance.
Simply select the hard drive partition to defragment and click "Continue". The tool does the rest by itself. Version 4.1 has bug fixes. You can find a list of all of the changes in the official release notes.
Verdict: It's a racing fast hard drive defragmenter, and it's also free. The developer also offers a portable version that doesn't require installation and runs directly from a USB drive.