IObit Smart Defrag is a powerful and highly efficient defragmentation tool suitable for all types of hard drives. It provides safe and fast optimization for your computer. The interface is very graphic and intuitive with tabbed menus for easier view of options. When you defragment your disc the system files that are in use can't be moved but the Boot Time defragment option allows you to completely defragment when you later restart your computer. You can also set automatic scheduled defragmentation for regular optimization of your drive and computer.