A jacuzzi and a whirlpool are essentially the same kind of pool used to generate swirling hot water. The only real difference is that jacuzzi is a specific brand name, albeit one that has become most recognised. A jacuzzi is a whirlpool, but not every whirlpool is a jacuzzi.
Jacuzzi was the one who invented the whirlpool tub in the late 1950s. Candido jacuzzi used his family's expertise in air jet pumps to develop a water pump for bathtubs. This was to help his son Ken receive at home the hydrotherapy he got for his arthritis at the hospital. The first pumps were sold in 1955, and tubs with jets preinstalled came soon after.
Use and History
The whirlpool tub is a large bathtub of warm to hot water in which water is circulated and shot into the pool through small jets. The constantly moving and swirling hot water was primarily used for physical muscle relief. Whirlpool tubs were first used in hospitals and then moved into gyms and health clubs. During the 1980s, the desire for whirlpool tubs in homes grew.
A "hot tub" is another name for this type of tub; all jacuzzis and other whirlpools are essentially hot tubs. A hot tub may not be a whirlpool, however. There are hot tubs without the jets of shooting water that are specific to whirlpools. Whirlpools are always stationary -- due to the electrical equipment needed for the jets -- while some types of hot tubs can be portable.
Jacuzzi has joined a long line of brand names that are colloquially associated with the product, thus causing many people to reference every product by the name. This includes Xerox for photocopying, Q-tip for cotton swabs, Band-Aid for bandages and AstroTurf for synthetic grass. This can be beneficial to the original name in a small way, as it is free advertising. It may be frustrating, however to a different manufacturer that wants to separate its product.