Computers delete data by overwriting it with new information. This process is not as simple as erasing a file from your hard drive. Instead, it involves changing the data that's stored in the designated memory space.
Here's how it works:
- Marking a file as deleted: When you delete a file, your operating system doesn't immediately erase the data. Instead, it simply marks the file as deleted in a directory table. This table acts as a map for your computer to find files on your hard drive. By marking the file as deleted, the operating system tells the computer to ignore that particular file.
- Overwriting the data: The space occupied by the deleted file is now available for new data. However, the original data remains on the hard drive until it's overwritten by new information.
- Data recovery: This is why deleted files can sometimes be recovered using data recovery software. These programs can scan your hard drive and attempt to recover data that has been overwritten or marked as deleted.
There are different methods for deleting data, including:
- Secure deletion: This method involves overwriting the deleted data multiple times with random data, making it much harder to recover.
- Data shredding: This is a more secure method of deleting data that overwrites the data multiple times using specific patterns. This process makes it almost impossible to recover the deleted data.
In summary, computers delete data by marking files as deleted and then overwriting the space with new data. While deleted files can be recovered in some cases, secure deletion and data shredding methods offer more robust protection against data recovery.
