Neon signage is the craft of bending glass tubing into shapes, which are then evacuated of air until they have reached near-vacuum and then filling them with Neon, Krypton, Argon, Xenon, or Helium gas and, in some cases, a droplet of Mercury.

Signs usually tend towards using Neon (which glows orange-red) or Krypton and Mercury (which glows sky blue). Different gasses find more usage in the field of Illuminated Art.

Other colors are obtained by using colored glass tubing and tubing that has been coated with a Phosphor and possibly a pigment powder.

They are illuminated by either a transformer or a switching power supply running at voltages ranging between 3000 and 15000 volts and between 30 and 120 mA.

Neon signs are a type of Cold Cathode lighting.

The light-emitting tubes form colored lines with which a text can be written or a picture drawn, including various decorations, especially in advertising. By programming sequences of switching parts on and off there are many posibilities for dynamic light patterns.

'['See also Timeline of lighting technology, Neon, 1911 in science