A lamp dimmer is an electrical device used to control the brightness of a lamp or a group of lamps. A dimmer switch allows you to adjust the amount of power flowing to the lamp, which in turn adjusts the brightness of the light. This can be useful for creating a warm, cozy atmosphere, or for conserving energy when full brightness is not needed. Dimmers are typically installed in place of a standard light switch and are wired in the same way. There are various types of dimmer switches, including rotary dimmers, slide dimmers, and touch dimmers, and they are available for both incandescent and LED lamps. Installing a dimmer switch requires electrical wiring knowledge and experience, so it is usually best to consult with a professional electrician if you are not confident in your abilities.