In this article an attempt is made to remove some of the confusions that may block understanding of the digital computer, its use and its application to the surveying profession. An outline of the history of electron data processing is given from the earliest concepts of numerical symbols and mechanical accounting machines to the present levels of technological skills. The various functional components that collectively form a data processing system are described in simple and non-technical terms. Data representation and storage devices are considered in order to introduce a typical data processing system. Data processing methods and user responsibilities are emphasized to highlight data processing justification.More importantly the article is intended to help surveyors understand the part that electronic data processing could play in the successful introduction of the “Integrated Survey System" into New South Wales. Hence the objective of this article is educational and informative rather than technically detailed. © 1971 Taylor & Francis Group, LLC.