Vacuum strength is a measure of the suction power of a vacuum cleaner. It is determined by the amount of air that can be moved through the vacuum's hose and nozzle in a given amount of time. Suction is the term used to describe the force created by the vacuum cleaner as it pulls air and dirt particles into the machine. The higher the suction power, the more effective the vacuum cleaner will be at removing dirt and debris from carpets and other surfaces.