At its core, the machine uses a heating block or a small boiler to heat cold water. After you load the coffee grounds into the portafilter and tamp them firmly, you activate the extraction switch. The machine’s internal pump then pushes the heated water through the compacted coffee puck at a certain pressure (typically up to 15 bar or higher), extracting a cup of espresso rich in crema within 20–30 seconds.
Afterwards, you can switch to steam mode and use the generated steam to heat and froth milk, creating milk foam for milk-based coffee drinks.