In Windows 10 you will no longer need to defragment your HDD with a defrag tool. Windows 10 automatically defragments your HDD in background on scheduled basis when your PC is idle. Also SSDs are trimmed automatically in Windows 10 ...
Windows 7 just like older versions of Windows defragments the system files at startup. If you have installed Windows on a SSD drive you will no longer need this! Because SSD drives can read files from random locations instantly unlike Harddisks ...