If you erase the hard drive you'll remove everything from it, INCLUDING Windows. (i.e. you'll have to reload Windows again AND all of your device drivers). Are you ABSOLUTELY sure that's what you want to do? If so, you can't do it directly from within Windows. You need to ensure that your computer's BIOS is configured to boot from a floppy disk or CD and then start your computer with such a disk, containing something like DBAN , already in the relevant drive.
To wipe a hard drive means to completely erase the drive of all information. Deleting everything does not wipe a hard drive and formatting does not [always] wipe a hard drive. You'll need to take an extra step to wipe the hard drive completely.
When you format a hard drive or delete a partition, you're usually only deleting the file system, making the data invisible but not gone. A file recovery program or special hardware can easily recover the information.
If you want to make sure that your private information is gone forever, you'll need to wipe the hard drive using special software.
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