The airbrush paints are designed solely for your airbrush equipment. It also should be brought to attention that artists that use airbrush paints are not limited to just these colors. It is possible to use any liquid/paint as long as it can be thinned down to a lighter consistency, so it will be easier to spray through the airbrush nozzle. These types of paints can include watercolor, gouache, acrylics, and oil paints.
The water color paints are, as the name implies, water based and best suited for use in an airbrush device. Typically, these water color paints are available in pre-reduced that are ready for immediate use in the airbrush.
The acrylics style paint comes in both transparent and opaque colors, but make sure to use one that is geared more towards use in the airbrush, as cleaning will become an issue if you purchase a different form of acrylic paint.
The final type of airbrush paint that is used by artists is oil based paints. Also sold under the Tempera name, it is also water based but has a white pigment added to the oil to make the paint appear more opaque. Typically, the oil based airbrush paints are gear more towards the advanced artist because the cleanup takes up the majority of time.