Lighting, also known as illumination, is the deliberate use of light to achieve a practical or aesthetic effect. Lighting includes the use of both artificial light sources such as lamps and natural illumination of interiors from sunlight. Proper lighting can enhance task performance, improve the appearance of an area, or have positive psychological effects on occupants. Indoor lighting is usually accomplished using light fixtures, and is a key part of interior design. Lighting can also be an intrinsic component of landscape projects. Lighting not only helps to illuminate the way but also sets the mood and atmosphere of the space. Lighting technology has evolved significantly over the past several decades. The most common forms of lighting used in modern times are: incandescent lighting, which utilizes a wire filament and a gas-filled bulb; fluorescent lighting, which use phosphors mixed with gases in a tube; and LED lighting, which use semiconductor diodes for efficient light production. In addition to artificial light sources, daylight is sometimes used as a lighting source. Daylighting provides uniform illumination throughout an area and can be used in a variety of areas, such as classrooms, retail stores, and homes. Daylighting is an effective way to reduce energy consumption and is an increasingly popular lighting option. Regardless of the types of light used, proper lighting enhances a space and makes it more comfortable and inviting. Attention to detail with lighting can make a world of difference in the overall look and feel of a space.