There are four principal types of machines piston, semi-automatic, fully automatic, and super automatic. PISTON is the classic espresso machine. It was developed to generate the eight to nine times of atmospheric pressure needed to force water through the coffee to make a perfect espresso. Generally, these machines are only suited to low throughput venues. They require a lot of practice to produce good coffee because exerting the correct and consistent pressure on the lever operating the piston is essential. However, they beautifully depict the ritual of making coffee. SEMI-AUTOMATICS were first introduced in the 1940s and removed the human frailties of pulling a lever by having electric pumps to produce the brewing pressure. Most have switches to start and stop the pumps and the extraction process normally takes around 20 to 25 seconds. Most have a separate reservoir for boiling the water and can therefore also be used for making tea and other hot drinks. More modern machines don't have a reservoir, instead they have electric coils that heat the water on demand as it passes through. Frothing, essential for creating cappuccino, latte, mocha and the like, is achieved either by an adapter or a steam wand. Most experts says the wand is easier for newcomers to master. FULLY AUTOMATICS work on a one-touch principle, which means employees do not have to stand over the machine while extraction takes place. The ease of use is very good and the learning curve is medium. Frothing systems are generally the same as semi-automatics. SUPER AUTOMATICS take all the sweat out of preparing good quality coffee and are proving to be the most popular type of machine for that very reason. They perform the entire process in a fraction of the time. They have water reservoirs and integrated coffee grinders and a simple push of a button is all that's needed. They will grind the correct quantity of beans, tamp the ground beans, extract a pre-determined amount of coffee, and dispose of the used coffee into an internal dump box. Certain models will even help the user maintain the machine. Some super automatics allow the operator to control the coffee strength to make weaker or stronger espresso, or doubles. An added feature can be a facility to bypass the grinder useful for pre-ground coffee or customers that want decaffeinated coffee With super automatics, frothing is simple and many can supply steam continuously. Maintenance and cleaning requirements are the lowest of all types of machine.