Major types of Air Filters

[HEPA]

There are a few different methods of air cleaning, like Filtration, Electro-static Precipitation and Ion Generation.
There are four major types of air filters:-depending on specific needs.

Mechanical Filters
These filters force air through a special screen that traps pollen, dust particulate, smoke and air-borne irritants and pet dander.

Gas Phase Filters
These air filters are used for removing odors and other types of pollutants such as gases from cooking, paints, perfume etc.

Electronic Filters
Electronic filters use electric charges to attract contaminants.

Hybrid Filters
These air filters combine electrostatic and mechanical filters. These are used to trap allergens rather than gas based contaminants.

[Money_maker]

I think Mechanical Filters use in AC and splits?