What is the purpose of hashing in digital forensics software like FTK Imager?

Hashing in digital forensics, particularly in tools like FTK Imager, is primarily used to verify the integrity of data. When data is hashed, a unique fixed-size string of characters, known as a hash value, is generated based on the contents of that data. This hash value acts as a digital fingerprint of the original file or disk image.

During the forensic process, after an image has been created, the hash of that image can be calculated and compared to the original source's hash value. If the two hash values match, it confirms that the data has remained unchanged and has not been tampered with during the imaging process or any subsequent analysis. This integrity verification is crucial in a legal context, as it ensures that the evidence presented is reliable and has not been altered.

The other choices involve processes that either do not pertain directly to the purpose of hashing or are not functions of digital forensics software. For instance, compressing images, increasing speed, or changing file formats are not the primary goals of hashing. Instead, hashing serves the essential function of ensuring that data integrity is maintained throughout the forensic examination process.