There are 3 forms of hydroponics they are Agroponics, Aeroponics and Aquaponics.

The definition of hydroponics is literally working water…or as used today the science of growing plants without soil.

A solid, inert medium such as coconut coir, vermiculite or perlite that provides support for the plant roots. As in liquid systems, the nutrient solution is delivered directly to the plant roots.

The process of growing plants in an air or mist environment without the use of soil or an aggregate medium

The symbiotic cultivation of plants and aquatic animals in a recirculating environment.