DEVICE: http://whatis.techtarget.com/definition/device
http://www.webopedia.com/TERM/D/device.html
PERIPHERAL DEVICE: http://www.webopedia.com/TERM/P/peripheral_device.html
INPUT DEVICE; http://www.webopedia.com/TERM/I/input_device.html
OUTPUT DEVICE: http://www.webopedia.com/TERM/O/output_device.html
more information:
a brief history of computing device http://trillian.randomstuff.org.uk/~stephen/history/timeline-MECH.html