called . Nodes can be moved or deleted by the usual filesystem system calls (, ) and commands (, ). Some Unix versions include a script named makedev or MAKEDEV to create all necessary devices in the directory . It only makes sense on systems whose devices are statically assigned major numbers (e.g., by means of hardcoding it in their kernel module). While some other Unix systems such as FreeBSD, used kernel-based device node management via devfs only, and not supporting manual node creation. system call and command exist to keep compatibility with POSIX, but manually created device nodes outside devfs will not function at all. Naming conventions The following prefixes are used for the names of some devices in the hierarchy, to identify the type of device: : line printers (compare lp) : pseudo-terminals (virtual terminals) : terminals Some additional prefixes have come into common use in some operating systems: : frame buffer : (platform) floppy disks, though this same abbreviation is also commonly used to refer to file descriptor : ("classic") IDE driver (previously used for ATA hard disk drive, ATAPI optical disc drives, etc.) : the master device on the first ATA channel (usually identified by major number 3 and minor number 0) : the slave device on the first ATA channel : the master device on the second ATA channel : the slave device on the second ATA channel , : parallel ports : Main memory (character device) NVMe driver: : first registered device's device controller (character device) : first registered device's first namespace (block device) : first registered device's first namespace's first partition (block device) MMC driver: : storage driver for MMC media (SD cards, eMMC chips on laptops, etc.) : first registered device : first registered device's first partition SCSI driver, also used by libATA (modern PATA/SATA driver), USB, IEEE 1394, etc.: : mass-storage driver (block device) : first registered device , etc.: second, third, etc. registered devices : Enclosure driver : generic SCSI layer : "ROM" driver (data-oriented optical disc drives; scd is just a secondary alias) : magnetic tape driver : terminals : (platform) serial port driver : USB serial converters, modems, etc. The canonical list of the prefixes used in Linux can be found in the Linux Device List, the official registry of allocated device numbers and directory nodes for the Linux operating system. For most devices, this prefix is followed