Translations:Device file/17/en
From Gentoo Wiki
udev creates for some device classes additional symlinks. The device file /dev/cdrom (first CD-ROM drive) and /dev/dvd (first DVD drive) are just symlinks to the device file /dev/sr0 (first optical drive). You can use the symlinks in programs and config files like every other device file. Other examples are /dev/input for input devices or /dev/disk for storage devices.