Hard Disk Drives, or HDDs, are a type of data storage device that use spinning disks coated with magnetic material to read and write data. They have been a staple in computers for decades, providing a reliable way to store large amounts of information, from operating systems to personal files. Despite the rise of Solid State Drives (SSDs), HDDs remain popular due to their cost-effectiveness and high storage capacity. They are commonly used in desktops, laptops, and servers, making them essential for both personal and enterprise-level data management.