Lynn Poole shows photos of a variety of computers from desk-size to house-size. Dr. Robert Rich, supervisor of the computer center at Johns Hopkins University's Applied Physics Lab, explains the workings of an electromechanical punch card accounting system, which is an externally programmed device. He shows an oversized punch card and photos of keypunch, sorting, and accounting machines. He notes that this process has speed limitations, but internally programmed computers have both speed and versatility of input. Dr. Rich describes the operation of a model of a UNIVAC business computer, which he says resembles an IBM 700 or Datamatic 1000. Such a computer is most efficient in routine computations on large numbers of data for such purposes as banking, weather forecasting, inventory control, etc. Scientific applications, such as missile flight paths, require a human programmer to write complex sets of instructions for the computer.