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Incandescent lamps, otherwise known as light bulbs, have been around for more than a century. They are the basic form of electric lighting–a glowing wire, usually made of tungsten, that produces light when an electric current is passed through it. The wire, or filament, is sealed within an evacuated, airtight glass bulb, then filled with an non-reactive gas, usually nitrogen or argon.

Incandescent lamps are usually powered by an AC current, although DC voltage can be used as well. When the filament is heated to temperatures of around 5,400°K, the emission of electrons accelerates, emitting visible light. This means that the bulb’s electrical rating must have enough capacity for these higher temperatures, since the electric power increases with temperature.

The most common and inefficient type of incandescent lamp uses a tungsten wire filament that is placed in a paper or plastic bag that is then placed in a glass envelope. Over time, the filament will darken, reducing the amount of light produced. A more efficient design is the open-tube type, which has no paper or plastic bag. Instead, two supporting strips are placed in the glass envelope that support the filament and hold it in place. This design saves energy and produces a brighter light.

Neon lamps are another type of electric lighting, though they are less widely used than incandescent lamps. A neon lamp, or tube, is filled with a low-pressure mixture of noble gases, such as neon, argon, and krypton. When a current is applied to the tube, it produces visible light much in the same way as an incandescent bulb. The color of the emitted light is determined by the type and mixture of the noble gas used.

Neon lamps are generally smaller than their incandescent counterparts, and produce a warmer, softer light that is flattering for skin tones in large areas. They are often used for accent lighting and signage. Unlike incandescent or halogen lamps, neon lamps do not produce ultraviolet radiation, and therefore do not require a protective filter.

When designed properly, both neon and incandescent lamps are very efficient sources of light, providing excellent illumination with minimal energy consumption. They can be used to illuminate large areas such as showrooms, lobbies, or warehouses, or in smaller areas such as recessed lighting and accent lighting. Both types of lamps are found in a wide variety of applications, ranging from residential to commercial to industrial.