environmental
active
appliance
automatic
button
circuit
comfort
connect
contrast
control
detail
ease
electrician
electricity
electromagnetic
electronics
energy
equipment
grey
hardware
home
human
idea
illumination
illustration
indoor
industrial
interior
light
line
metaphor
off
play
power
press
push
realistic
residential
room
save
set
stop
supply
switch
technology
touch
turn
utility
voltage
white