Neon lights

Electric discharges through noble gases can produce light, particularly red light with neon. The fact that tubes filled with neon or other gases could be twisted into any shape—so that they spelled out words, made them appealing in advertisement.
 Georges Claude France 1910 Neon lights

Electric discharges through noble gases can produce light, particularly red light with neon. The fact that tubes filled with neon or other gases could be twisted into any shape—so that they spelled out words, made them appealing in advertisement.