Disk and file system (Simplified)

Physical disk composition

1. Round disks , Used to record data
   1. A sector , The smallest physical storage unit , Yes 512Bytes and 4K Two formats
   2. The circle composed of sectors is cylindrical
2. The robot arm and the magnetic head on the robot arm , Used to read and write data on disk
3. Spindle motor , Turn the disc , Let the magnetic head read and write data on the disk

In an indexed file system

1. Some of the concepts

1. superblock:  Record the overall information of the file system ,  Include inode/block Total amount , Usage quantity , Surplus quantity ,  And the format of the file system 
2. inode:  Record file properties ,  One file will occupy one inode, inode Where the file data is recorded block
3. block:  Actual recorded file contents 

Chained file system ( Such as FAT)

1. Every block The number is recorded in the previous block In the number