To delete unnecessary files on a hard disk use?

step by step

1. Open the Disk Cleanup by clicking Start, point to All Programs, point to Accessories, point to System Tools, and then click Disk Cleanup. Disk Cleanup will then calculate how much space you will be able to free on your hard drive.

2.Select the files by clicking the check box that you would like to delete (e.g. Downloaded Program Files and Temporary Internet Files) and click OK

3. Click Yes to confirm performing these actions.

To read the description of the particular program file, click the appropriate file and the file description is displayed at the bottom. If you want view the files on the particular program file (e.g. Downloaded Program Files and Temporary Internet Files), click View Files.

4. Click More Options tab to free up more space on Windows components, installed programs or System Restore. Click Clean up

what is your question exactly? when you let me know i will gladly you. : )

they really not common the os x is just a better version of the os like in iphone theirs xr and their xs