Lighting is the use of light to achieve a practical or aesthetic effect, as in the lighting of rooms, streets, and buildings. It is an important part of interior design and is related to architectural spaces, as well as domestic, workplace, or entertainment settings. It includes both natural and artificial sources of light, as well as the control systems by which it is switched on and off and modulated. Lighting typically refers to visible light, but in some applications, such as for plants, ultraviolet and infrared radiation may also be employed. A society's attitudes towards lighting affect how much money and energy are expended on lighting systems. This includes matters of energy efficiency, as well as people's visual preference. Lighting affects how people perceive their environment, both in terms of safety and security as well as the aesthetic visual appeal of a space. Good lighting contributes to our sense of comfort and well-being, supports the activities we engage in, and helps us appreciate the physical and social environment we inhabit. Lighting is also closely linked to architecture, as it can be used to enhance spaces, create atmosphere, and support the materials and textures employed in a space. Lighting can be a major source of energy use in homes, workplaces, and public spaces. To conserve energy, many jurisdictions have established energy standards to limit the amount of energy used for lighting. These standards set minimum requirements for lighting performance and energy efficiency, and they also offer incentives for using more efficient lighting systems and fixtures. For example, many jurisdictions offer incentives for switching from traditional incandescent bulbs to more efficient compact fluorescent lamps (CFLs) and light-emitting diode (LED) lamps.