The hard drive is the primary, and usually most substantial, data storage hardware device in a computer. The operating system, software titles, and most other files are stored on the hard drive.
How do hard drives work? 💻💿🛠
The hard drive is sometimes referred to as the "C drive" because by default, Microsoft Windows assigns the drive letter "C" to the primary partition on a computer's primary hard drive.
Although this is not technically a correct term to use, it is still common. For example, some computers have multiple drive letters (e.g. C, D, and E) that represent areas on one or more hard drives. The hard drive is also called HDD (the abbreviation), hard disk drive, hard drive, magnetic hard drive, mechanical hard drive, hard disk, and fixed disk.
Regardless of its name, the primary hard drive typically contains the root directory of the operating system in use.