udev is a modern replacement for devfs which was itself a replacement of a static /dev directory.
In essence, udev is a userspace application using the hotplugging capabilities of the Linux kernel which enables /dev to reside in RAM and contain ONLY existing devices.
It saves in disk space and in memory consumption. And it’s soooo nice to see only the real devices on the computer.
Configuration for Gentoo was a breeze (and it worked the first time around) using this detailed instructions.
Make the jump :-)