The dimmer switch is used to control the light intensity from high to low and low to high. These switches can be installed in different locations in the home like the kitchen, bathroom, bedroom, living room, etc. Dimmer switches are appropriate to use with halogen & incandescent lamps. A dimmer is a device connected to a light fixture and used to lower the brightness of the light. By changing the voltage waveform applied to the lamp, it is possible to lower the intensity of the light output.