How to Erase a Hard Disk Drive Completely?
The two most common ways to erase all this information on your hard disk drive is by formatting or wiping the drive or you can choose to physically smash the hard drive, physically destroying a hard drive or writing to it 3, 7 and even 25 times as the only reliable methods of getting rid of data. This really is not the case. Data is stored magnetically and are represented by 1′s and 0′s. In older hard drives it is possible to view previous states that these magnetic areas existed in. Such as a 1 used to be a 0. This is done with an electron microscope in the examples that I’m aware of. Even though this is possible, it would still be nearly impossible to get enough correct readings to put together a document, picture or anything else.
Erasing and Formatting
Using the delete key on your keyboard in Windows will only remove the shortcuts to the files making them invisible to users. Deleted files still reside on the hard drive and a quick Google search will show many options for system recovery software will allow anyone to reinstate that data. Regular file deletion does not really delete the contents of a file. On a Windows XP system this includes choosing a file and pressing the delete key to move it to the recycle bin. As well as the files emptied from the recycle bin and files deleted by holding down shift while pressing delete to bypass the recycle bin. Formatting the hard drive is a bit more secure than simply erasing the files. Formatting a disk does not erase the data on the disk, only the address tables. It makes it much more difficult to recover the files. However a computer specialist would be able to recover most or all the data that was on the disk before the reformat. A disk format may be something you consider secure enough depending on the type of data and information you saved to your computer. As long as people understand that formatting is not a 100 percent secure way to completely remove all data from your computer, then they are able to make the choice between formatting and even more secure methods. If you have decided a disk format is a good choice, at the very least to do a full format rather than a quick format.
Disk Wiping
Even more secure than reformatting is a process called disk wiping or disk scrubbing or disk wiping. Wiping a hard drive involves using software or a hardware device to completely write over every bit of a hard drive. This will prevent the recovery of nearly all data on that hard drive.. Disk wiping is a secure method of ensuring that data, including company and individually licensed software on your computer and storage devices is irrecoverably deleted before recycling or donating the equipment. Because previously stored data can be brought back with the right software and applications, the disk wiping process will actually overwrite your entire hard drive with data, several times. Once you format you'll find it all but impossible to retrieve the data which was on the drive before the overwrite. File wiping involves using software to completely write over the contents of a file. The entry for that file in areas such as the file allocation table is usually removed as well. Wiping files is better than pressing the delete key on your keyboard but remnants of these now wiped files can still be found in other places on the hard drive. This is especially true if the file is copied back and forth between volumes, has been cached to the disk from RAM and numerous other operations done by the operating system.
Disc Destruction
The simplest form of data destruction is simple overwriting of the entire hard drive. As mentioned above, wiping a modern hard disk once is enough to prevent recovery of data. Another simple method of data “destruction” is encryption. Encrypting a hard disk with full disk encryption will effectively render that data unreadable as if it had been overwritten with random characters. Degaussing is one of the best but most expensive methods. It involves using hardware which renders previous data on a hard disk unreadable by changing the magnetic alignment of areas of the hard disk. Another sure method is physical destruction to the platters inside of the hard drive. This can be done by smashing, grinding and shredding them. You can burn them and dip them in corrosive acid as well. Essentially, anything that can cause total destruction to the platters will destroy the data on them.
