In this chapter, we learned about John von Neumann's stored-program computer architecture, and its subsequent implementation in physical processors and chips. We also learned how supercomputers are classified using Flynn's classical taxonomy, depending on how the instruction and data stream are implemented in the final design. A historical perspective was provided to contextualize the genesis of supercomputers, and the current quest for even greater supercomputing power. We learned the mechanics behind serial processing and parallel processing, and why parallel processing is more efficient at solving complex problems - if the problem can be logically paralyzed employing MPI. We justified the need for greater processing speed by providing several examples of real-world scenarios such as auto assembly, jet construction, drive-thru lunch, rush hour traffic, plate tectonics, and weather, to list a few examples. Finally, an additional analytical perspective was provided to buttress the need for greater processing speed.