CHAPTER 1 OVERVIEW OF COMPUTER AND PROGRAMMING

1. CHAPTER 1OVERVIEW OF COMPUTER AND PROGRAMMING 1.1 Electronic Computer Then and Now 1.2 Computer Hardware 1.3 Computer Software 1.4 The Software Development Method 1.5 Applying the Software Development Method

2. 1.1 Overview of ComputerThen and Now 1st electronic computer – 1930 • Dr John Atanasoff and Clifford Berry • Iowa State University ENIAC • General purpose electronic digital computer • 1946 - University of Pennsylvania • 30 tons, 30 to 50 foot space • Used – compute ballistic table, predict the weather, make atomic energy calculations

3. 1.1 Overview of Computer Then and Now (Cont..) Computer category • Microcomputer • Workstations • Minicomputers • Mainframe • Supercomputer Elements of computer • Hardware – equipment / devices • Software • programs that enable us to solve problem with a computer by providing it with lists of instruction to perform. • Written by programmers

4. 1.2 Computer Hardware Components • Main memory • RAM (Random Access Memory) - Volatile • ROM (Read Only Memory) – Non-volatile • Secondary memory • Hard disk, floppy disk, magnetic disk, CD • Central Processing Unit (CPU) • Control Unit (CU) • Arithmetic Logic Unit (ALU) • Input Devices • Keyboard, mouse, microphone, • Output Devices • Monitor, speaker, printer

5. 1.3 Computer Software 2 types: • Operating system • Application software Operating system • Stored permanently –ROM • Example: • Command line Interface – UNIX, MS-DOS, VMS • Graphical User Interface – Macintosh OS, Windows 98/ XP, Windows NT Application Software • Develop to assist a computer user in accomplishing specific tasks. • Example : word processing, spreadsheet, Adobe

6. 1.3 Computer Software (Cont..) Machine Language /Low-level Language • Binary number – 0,1 • Computer understand High-level Language / Programming Language • Example: C, C++, Visual Basic, Cobol, Fortran Compiler / interpreter • The language translation software that convert a programmer’s statement to binary form Language syntax • Rules governing its word usage and punctuation.

7. 1.4 The Software Development Method Six (6) Software Development Method • Specify the problem requirement • Understanding required for its solution • Analyze the problem • Identify input, process, output • Design the algorithm to solve a problem • Develop a list of steps called algorithm • Pseudocode, Flowchart, N-S Diagram, Decision Table • Implement the algorithm • Convert algorithm to programming language • Test and verify the completed program • Compile  Run • Maintain and update the program

8. 1.5 Applying the Software Development Method • Problem • MengiraLuasSegiempat • Analysis • Input : panjang, lebar • Proses: Luas = panjang x lebar • Output : Luas • Design • Algorithm • Pseudocode • Implementation • Start get panjang, lebar Luas = panjang * lebar print Luas • Stop #include <stdio.h> int main() { intpanjang, lebar, Luas; scanf (“%d %d”, &panjang, &lebar); Luas = panjang * lebar; printf (“%d”, Luas); return 0; }