Which method exposes a hard drive to a powerful magnetic field to erase data?

Degaussing is the method that exposes a hard drive to a powerful magnetic field to erase data. This technique works by disrupting the magnetic fields that store the data on the hard drive, effectively rendering it unreadable. When a hard drive is degaussed, the data cannot be recovered through traditional means, as the physical state of the magnetic media is altered. This method is particularly effective for magnetic storage media, such as hard disks and magnetic tapes, and is commonly used in environments that require secure data destruction, such as government agencies and financial institutions.

Formatting and data wiping involve different processes, primarily focused on preparing the drive for new data or permanently deleting data in a way that makes it difficult to recover—but not necessarily rendering it completely unrecoverable like degaussing does. Encryption, on the other hand, is a protective measure that scrambles data to prevent unauthorized access but does not erase it. Thus, degaussing stands out as the definitive choice for the complete and irreversible erasure of data through a powerful magnetic field.