Ink jet printers operate by propelling variably sized droplets of liquid or molten material called ink onto almost any sized page. They are the most common type of computer printer for the general consumer due to their low cost, high quality of output, capability of printing in vivid color, and ease of use. Like most modern technologies, the present day ink jet has built on the progress made by many earlier versions. Many contributors can claim a substantial share of the credit for the development of the modern ink jet. There are various types of ink jet printer available worldwide. Thermal ink jets are most commonly used model in printing. Most consumer ink jet printers use print cartridges with a series of tiny electrically heated chambers constructed by photo lithography. To produce an image, the printer runs a pulse of current through the heating elements causing a steam explosion in the chamber to form a bubble, which propels a droplet of ink onto the paper. The inks surface tension as well as the condensation and thus contraction of the vapor bubble, pulls a further charge of ink into the chamber. There are several other technologies. One of the industrial dedicated printer technology is Piezoelectric ink jet. Most commercial and industrial ink jet printers use a piezoelectric material in an ink filled chamber behind each nozzle instead of a heating element. When a voltage is applied, the piezoelectric material changes shape or size, which generates a pressure pulse in the fluid forcing a droplet of ink from the nozzle. This is essentially the same mechanism as the thermal inkjet but generates the pressure pulse using a different physical principle. One more advanced printing method is continuous ink jet. The continuous ink jet method is used commercially for marking and coding of products and packages. The idea was first patented in 1867, by Lord Kelvin and the first commercial devices. In continuous ink jet technology, a high pressure pump directs liquid ink from a reservoir through a gun body and a microscopic nozzle, creating a continuous stream of ink droplets via the Plateau Rayleigh instability. In piezoelectric ink jet type, crystal creates an acoustic wave as it vibrates within the gun body and causes the stream of liquid to break into droplets at regular intervals. The ink droplets are subjected to an electrostatic field created by a charging electrode as they form, the field varies according to the degree of drop deflection desired. This results in a controlled, variable electrostatic charge on each droplet.