It can be. There are several factors that affect hard drive data security: who has access to the physical environment, what are your response procedures if the device is lost or stolen, and what are the regulatory security requirements are just a few things to consider. Yes, data on a computer hard drive can be very safe. But what happens if the computer fails? Is your data adequately backed up? Can you recover that data quickly, if need be? There are many safeguards and controls that can be implemented to protect your hard drive, including hardware encryption techniques and host-based security mechanisms.