Hard Disk Structure
Every hard disk consists of various cylinders, heads, and sectors. Every hard disk sector has 512 bytes. This is rather complicated and thus not suitable for users to save files on a disk in such a way.
The hard disk is first "formatted" to allow users to write files to that hard drive. This structures the many cylinders, heads, and sectors in such a way as to permit the storage of entire files. This structure is called a "file system."
The first hard disks appeared at the beginning of the 80s. At that time developers / users were only familiar with floppy disks. From that point of view, the space of a hard disk seemed very large. The developers thus decided to split large hard disks into smaller units or at least plan for partitioning large drives.
A file system is written to each of these partitions. Every user knows this file system under the term "drive." The Microsoft operating systems assigned letters such as C:, D:, etc. to these drives .
One of the reasons for dividing a hard disk is the size of the file systems. The other reason is the option of being able to utilize different file systems (e.g., one for DOS/Windows and another one for Unix/Linux).
The process of this division is called "partitioning."