1. Dry Vacuum Cleaner
A dry vacuum cleaner is defined relative to vacuum cleaners that use water as a filtration medium. Both bagged and dust cup vacuum cleaners fall into the category of dry vacuum cleaners.
2. Wet and Dry Vacuum Cleaner
A wet and dry vacuum cleaner adopts water filtration technology, with water serving as the medium to trap dust and fine debris in the dust collection cup. When no water is added to the dust collection cup, it can be used as a dry vacuum cleaner.