  In this introductory article a brief description of Quantum Field Theories
(QFT) is presented with emphasis on the distinction between strongly and weakly
coupled theories. A case is made for using numerical simulations to solve QCD,
the regnant theory describing the interactions between quarks and gluons. I
present an overview of what these calculations involve, why they are hard, and
why they are tailor made for parallel computers. Finally, I try to communicate
the excitement amongst the practitioners by giving examples of the quantities
we will be able to calculate to within a few percent accuracy in the next five
years.
