A Disk Wipe Overview

Disk erasing or sanitizing is beneficial for privacy, because files are not completely deleted when using an operating system's default delete function. In most of the file systems, the delete function consists of marking the space occupied by the file as free and updating file system allocation structures, leaving actual file contents intact on the storage media.

If there is continuous flow of read and write operations on the drive after this deletion, eventually this space will be assigned to other files and will be overwritten. However, if the those segments of the computer hard drive are not read and written upon often the data may remain intact and at risk for years. Data recovery software or disk forensic tools can easily mine the data from the drive.

Form this we can understand that the normal 'delete' command or deleting data from the recycle - bin is not a safe method for data removal.

To securely erase data we need to follow certain patterns or standards for disk sanitization, the patterns used for overwriting are mentioned below and are available to effectively remove magnetic remnants from the hard drive.

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