The hard disk is a hardware device that stores all the data on a computer. The data is stored in the form of files and directories in the hard disk. A hard disk drive has a logical structure that is compatible with the operating system installed. Read on for a full explanation of the logical structure of a hard disk.
When you use your computer, your data is organised in the form of files and directories according to a tree structure and these are stored on your hard drive. Your operating system manages all this data on your hard drive. Consequently, a hard disk must have a particular organisation, understandable to your system.
The Master Boot Record is the most important part of the hard disk. It is the first sector on the hard disk that the operating system accesses. The Master Boot Record contains the Boot Loader and Partition Tables. It is important to know about the logical structure of the hard disk to gain better understanding and fix issues related to the hard disk drive.
The Magic Number is two bytes used to determine if the hard disk has a bootloader or not. If it does, the magic number should be equal in value to hexadecimal 55AA.