A vacuum cleaner is a device that uses an air pump to create a partial vacuum to suck up dust and dirt, usually from carpeted floors. Most homes with carpeted floors in developed countries possess a domestic vacuum cleaner for cleaning. The dirt is collected by a filtering system or a cyclone for later disposal. There are a few different kinds of vacuum cleaners that are available, and they are...
Upright vacuum cleaners: These have the pump mounted directly above the suction intake, with the bag mounted on the handle, which rises to about waist height. Upright designs usually employ mechanical touch rs, often rotating brushes, to help disturb dust to be vacuumed up; these touch rs are usually driven by a belt attached to the vacuum motor.
Canister (or cylinder): these vacuum cleaner designs have the motor and bag in a separate canister unit (usually mounted on wheels) connected to the vacuum head by a flexible hose. Although upright units have been tested as more effective (mainly because of the touch rs), the lighter, more manoeuverable heads of canister models are popular. Some upmarket canister models have "power heads", which contain the same sort of mechanical touch rs as in uprght units, although such touch rs are driven by a separate electric motor.
Back-pack vacs: These vacuum cleaners are commonly used for commercial cleaning: they allow the user to move rapidly about a large area. They are essentially canister vacuum cleaners, except that straps are used to carry the canister unit on the user's back.
Built-in or central vacuum cleaners: These move the suction motor and bag to a central location in the building and provide vacuum inlets at strategic places throughout the building: only the hose and pickup head need be carried from room to room; and the hose is commonly 8 m (25 ft) long, allowing a large range of movement without changing vacuum inlets. Plastic piping connects the vacuum outlets to the central unit. The vacuum head may either be unpowered or have touch rs operated by an electric motor or air-driven motor. The dirt bag in a central vacuum system is usually so large that emptying or changing needs to be done less often, perhaps once per year.
Robotic vacuum cleaners: Robotic vacuum cleaners move autonomously, usually in a mostly chaotic pattern ('random bounce'). Some come back to a docking station to charge their batteries, and a few are able to empty their dust containers into the dock as well.
Small hand-held vacuum cleaners: Either battery-operated or electric, these vacuum cleaners are also popular for cleaning up smaller s herbs .