A Brief History of Computers

We might begin this discussion with the following question Why do you want to calculate something The answer to this question, as given by Lord Kelvin, president 

Molecular Structure Understanding Steric ami Electronic Effects from Molecular Mechanics, 

Part of the potential importance of computers was recognized very early, although the only use foreseen originally was for calculations that were intensely numerical. For example, when asked about a potential usefulness of computers, Thomas Watson the chairman of IBM, stated in 1943, I think there is a world market for maybe five computers.  

Surely the invention and development of the electronic computer should be regarded as one of the most important developments in human history. This recalls the statement made by Commissioner Charles H. Duell of the U.S. Office of Patents in 1899. He recommended that the patent office be closed because everything that can be invented has been invented. Fortunately, Congress reacted by doing what they often do—they did nothing. For further information on the history of the giant computers, the book by Waldrop may be examined.  

From the point of view of the computational chemist. Digital Equipment deserves special mention. The machines listed prior to the mid-1980s were so-called mainframes, very expensive machines housed in computer centers Typically, a university or large 

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The Second Industrial Revolution - A Brief History of Computing... 

In the second section we present a brief overview of some currently used dynamic modeling methods before introducing cellular automata. After a brief history of this method we describe the ingredients that drive the dynamics exhibited by cellular automata. These include the platform on which cellular automata plays out its modeling, the state variables that define the ingredients, and the rules of movement that develop the dynamics. Each step in this section is accompanied by computer simulation programs carried on the CD in the back of the book. 

Ott, Martin A., Noordik, Jan H. 1992. "Computer Tools for Reaction Retrieval and Synthesis Planning in Organic Chemistry A Brief Review of Their History, Methods, and Programs." Recueil des travaux chimiques des Pays-Bas, lll(June) 239-246. 

The thesis begins with Section 2, where a brief history about the explicitly correlated approaches is presented. This is followed by Section 3 with general remarks about standard and explicitly correlated coupled-cluster theories. In Section 4, the details about the CCSD(F12) model relevant to the implementation in TuRBOMOLE are presented. The usefulness of the developed tool is illustrated with the application to the problems that are of interest to general chemistry. A very accurate determination of the reactions barrier heights of two CH3+CH4 reactions has been carried out (Section 5) and the atomization energies of 106 medium-size and small molecules were computed and compared with available experimental thermochemical data (Section 6). The ionization potentials and electron affinities of the atoms H, C, N, O and F were obtained and an agreement with the experimental values of the order of a fraction of a meV was reached (Section 7). Within all applications, the CCSD(F12) calculation was only a part of the whole computational procedure. The contributions from various levels of theory were taken into account to provide the final result, that could be successfully compared to the experiment. 

The starting point for the history of computers is unclear, and it can be selected almost arbitrarily, becanse so many separate technical developments were necessary before they could all come together to create the modem computer. Also, unlike many other technical developments, one cannot point to a single inventor to give the credit - it is really much more complicated than that. The following chapter is intended as a very brief summary of key developments and the names of those principally involved. However, any condensed summary such as this will almost inevitably be invidious, and doubtless some key names have been omitted, for which I apologize. 

The history of computing really begins with ideas for mechanical calculating devices and machine programing, long before electronics existed. These ideas originate at the time of the first industrial revolution, or even earlier. A very brief and selective historical overview follows. Many will no doubt think this is too selective, or too short. 

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