Devices and Printers can be accessed through Hardware and Sound > Devices and Printers in the Control Panel

 

Basically it is a centralized location to see all of the external devices connected to your computer, either via USB, network, or wirelessly - such as printers, external hard disks, cameras, portable music players, mobile phones, keyboards, mice etc

 

From here you can use them, remove them, change settings and troubleshoot them if not working correctly