While computer hardware configurations vary widely [2] , a Computer repair technician that works on OEM equipment will work with five general categories of hardware; desktop computers , laptops , servers , computer clusters and smartphones / mobile computing devices. Technicians also work with and occasionally repair a range of peripherals , including input devices (like keyboards , mice , webcams and scanners ), output devices (like displays , printers , and speakers ), and data storage devices such as internal and external hard drives and disk arrays. Technicians involved in system administration might also work with networking hardware , including routers , switches , cabling , fiber optics , and wireless networks . OEM = Original Equipment Manufacturer .