Abstract: This paper describes the concepts and technology of EXT2 file system from a developer's view, such as superblock, group descriptors, block bitmap of the group, i node bitmap of the group, i nodes of the group, data blocks of the group and root directory etc.Taking a file system maker for 1.44MB floppy disk as an example, the design and implementation of a Linux based EXT2 file system maker is discussed.The floppy disk formatting program is successfully implemented on an Ubuntu10.04 Linux PC based on Intel Pentium Ⅳ CPU, the formatted floppy disks can be used on operating systems that support EXT2.