Markets are interdependent upon each other. Demand can be looked upon as a "pull" system where entities higher up in the chain create demand on those immediately beneath them. These demands in turn create demands that cascade down through the system, layer-by-layer, in a sort of waterfall.
Another source of demand, however, is generated through a "push" system where technology makes available new resources that improve the ability of those higher in the chain to produce products and services and to generate more revenue. Specifically:<
Demand for electronics stimulates demand for semiconductor devices that stimulate demand for manufacturing equipment—this is "pull".