Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 1 Introduction

Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 2 A Brief History of Computers –Charles Babbage builds Analytical Engine in mid- 1800’s made from axels and gears that could store and process 40 digit numbers –1940 Howard Aitken at Harvard, and Atanasoff and Berry at Iowa State create Mark I, an electronic computer. It could not act on intermediate results. –1945 Mauchly and Eckert at U. Pennsylvania build the ENIAC Electronic Numerical Integrator and Calculator Weighed 33 tons, 17,000 vacuum tubes 5000 additions per second

Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 3 –1955 There are 300 computers in the world build mostly by IBM and Remington Rand, based on vacuum tubes. –Late 1950s and 1960 computers are based on the transistor, the first solid-state computers. –DEC creates the Minicomputer – about the size of a file cabinet. –Mainframes, such as the IBM 360 are prominent in large companies and Universities. –Late 1970s. The Personal computer becomes available with advances in microchip technology. –Microsoft and Apple are formed

Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 4 Currently: –PCs: 95% use Microsoft Windows operating system. Huge array of software available. –Minicomputers are still popular with small business and Universities. –Mainframes are in use at large corporations. – Supercomputers – very powerful and specialized for massive computing problems used by corporations and government departments.

Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 5 Computer Basics Components of a computer –CPU Central Processing Unit –Internal memory RAM (Random Access Memory) ROM (Read Only Memory) –Mass storage device Hard disk drives, floppy disk, CD, DVD –Input devices – keyboard and mouse –Output Devices – monitor and printer

Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 6 Basic Units of Memory –1 bit (0 or 1) –1 byte -> storage for one character –2 10 bytes =1024 bytes = 1 kilobyte (KB) –1024 KB = 1 megabyte (MB) –1024 MB = 1 gigabyte (GB) –(Many people will approximate to steps of 1000, not 1024)

Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 7 Software and Programming Languages Application Software –Word Processors –Database Managers –Spreadsheets –Photo Editors –Web browsers, programs System Software –Operating systems – Windows, DOS, Linux, UNIX

Introduction Extended and Concise Prelude to Programming Concepts and Design Copyright © 2003 Scott/Jones, Inc.. All rights reserved. 8 Programming Languages –Machine Languages –Assembly Languages ADD A,B –High-level Languages Look more like English words and algebraic expressions –Examples of High Level Languages ADA BASIC C++ COBOL Java Pascal Visual Basic