Device file
interface to a device driver that appears in a file system as if it were an ordinary file; e.g. /dev/* in Unix-like systems; CON, PRN, NUL in DOS/Windows
In some operating systems, a device file or special file is a file on the file system that can be used to access and control devices, such as printers or scanners. This is common on UNIX-like operating systems such as Linux.