How does a vacuum work?

How does a vacuum work is based on physics of air pressure difference created by electric motor and fan. Inside vacuum cleaner, electric motor spins fan at high speed, which pushes air out of machine through exhaust port, lowering air pressure inside chamber and creating partial vacuum. Outside air is at higher atmospheric pressure, so it rushes into machine through intake nozzle to equalize pressure, carrying dirt, dust, and debris with it. At nozzle, brush roll agitates carpet to loosen dirt. Dust-laden air travels through hose into filtration system where dust is separated by bag that traps particles or cyclonic separation that spins air to fling dirt out using centrifugal force, as in Dyson. Cleaned air passes through filters including HEPA filter that captures fine allergens, then exits machine. In bagless models, dirt collects in dustbin. Robot vacuums use same principle with smaller motor and sensors for navigation. So vacuum works by creating low pressure inside, causing high pressure outside to push air and dirt into machine, where dirt is trapped and clean air expelled.