How do you make neon signs?

A glass tube, emptied of all gases inside, is partially filled with a noble gas, such as Neon. A very high voltage is applied to two electrodes at both ends of the tube. Low pressure gas breaks down under the influence of te high field, and Neon molecules are accelarated and gain energy. As they travel they lose some of this energy in the form of photons, or light, at a very particular wavelength, characterisitic of the particular gas in the tube. Diferent compositions of gases may emit different colors of light.
i dont no do you?? :P