Lecture 34

= Origins of the Computer =

Introduction
Due to the fact that the U.S. has a shortage of skilled labourers compared to Europe, there is a strong emphasis on labour-saving technology. At the same time there is a population explosion during the latter half of the 19th century which requires census-taking programs. It was Herman Hollerith (1859–1929) who started the Tabulating Machine Company (1896), which later became I.B.M., in order to sell equipment to the U.S. government to fulfill the need for a means of storing and tabulating census data.

Calculating Machines
Calculating machines come in two varieties:


 * analog:
 * slide rule
 * planimeter (for finding the area under curves; integration)
 * digital:
 * abacus
 * electronic calculator

Analog machines represent numbers as physical quantities, i.e. one creates a physical model of the thing you wish to computer. These machines reached their zenith from the 1920s to the 1940s. As an example consider the differential analyzer which was used to calculate the fourier coefficients for systems of equations. These calculations involved integrals, so these devices were essentially fancy planimeters.