Disk Cleanup
Disk Cleanup is a Microsoft software utility first introduced with Windows 98 and included in all subsequent releases of Windows. It allows users to remove files that are no longer needed or that can be safely deleted. Removing unnecessary files, including temporary files, can help to speed up and improve the performance of the hard drive and computer. Running Disk Cleanup at least once a month is an excellent maintenance task and frequency.
Defrag
Defrag is a Microsoft utility first included with MS-DOS 6.0, and in all versions of Windows. It is designed to help chronologically order the data on the hard drive. Defrag places each part of a program together instead of scattered throughout the hard drive, allowing the read-write head to access the data faster on the hard drive.