EXT3 is the third-generation extended file system commonly used in the Linux operating system.

block is composed of a number of consecutive areas, block number starting from 1, the overall number, grouping

Each i node corresponds to a 1GE file or folder, which stores the description file size, file storage location and other information

The block group consists of a number of consecutive blocks, the number within the block group is determined by the block size

The superblock stores the basic information about the EXT3 file system