James Dyson, like many others, had to keep replacing the dust bags in his vacuum cleaner, even if they weren't full. When he got fed up of this, he thought of inventing a new vacuum cleaner with a new mechanism that would avoid this annoying task. The technique of particle separation using centrifugal force is common. Based on this principle, Dyson invented the vacuum cleaner that used cyclonic separation. The first Dyson vacuum cleaner, the G force, dawned in 1990. It also won the 1991 International Design Fair Prize in Japan. This product impressed the Japanese to such an extent that they licensed the product and sold them for a whopping $2,000 each. The first vacuum cleaner by Dyson was an upright model and the second was his first canister model. Introduction of every new model signified either a new technological innovation or revision of an existing model. The newer innovations included lightweight, low profile upright cleaners, robotic vacuum cleaners, upright model with Dyson Root Cyclone technology, cylinder model incorporating the Dyson Root Cyclone, telescopic wand handle and hose wrapping around the machine, cylinder model incorporating telescopic wand handling and hose wrap, etc. What sets apart Dyson from the rest is the distinctive Cyclone feature. Dyson cleaners are available in a wide range of bold colors like red, blue, green and also metallic colors. Each Dyson cleaner sports a unique external design. Most designs are sleek and compact. Subsequently, Dyson has also introduced several ergonomic features such as replacement of the wheel by a ball for easier movement.