Espresso are made by driving a pressurized amount of hot water through a pack of finely ground coffee powder. The characteristic of an espresso is reddish-brown foam on top. Current espresso machine are much more convenience then old espresso machine which uses manual power to generate the pressure needed for the brewing of the espresso. The word espresso give us the impression of fast which is true as if you are using a good espresso maker it would only around a minute for a shot of espresso. The reason as to why the espresso is so popular may be because the caffeine level in a shot of espresso is three times higher compared to a regular cup of coffee.