If you suffer with asthma or a dust allergy, the filtration system should be an important factor to determining which vacuum cleaner you'll buy. This is because the filtration system will determine the size and number of dust particles that'll be in the air when it is exhausted out of the vacuum.
A high wattage (input power) doesn't always mean better suction because the amount of this power that's turned into air watts (suction or output power) depends to some extent on the vacuum's design and efficiency.
The history of vacuum cleaners in the UK dates back to the early 1900s. Hubert Cecil Booth started the first vacuum cleaner company in the UK, known as the British Vacuum Cleaner Company. It wasn't long however before William Henry Hoover, who had already experienced success with his vacuum cleaners in America, made headway in the vacuum cleaners market in the UK and overtook Booth.