To choose which type of device to create, use one of the following arguments:
Create a FIFO file (named pipe). You do not need to specify the major and minor device numbers.
Create a block file. You must specify the major and minor device numbers the file represents.
Create a character file. You must specify the major and minor device numbers the file represents.
Linux's /dev/MAKEDEV utility is useful for creating one or more devices of a given type in a single command