By Kundang K Juman Hardware & Software

COMP102 Prog. Fundamentals I: Software / Slide 2 l Four components of a computer system: n CPU - central processing unit –Makes decisions, performs computations, and delegates input/output requests n Memory: Disk Drives, CD drives, Tape drives, USB flash drives. –Stores information n Input devices: Keyboard, Mouse, –Gets information from the user to the computer n Output devices: monitor –Sends information from computer to the user Hardware

COMP102 Prog. Fundamentals I: Software / Slide 3 Hardware

COMP102 Prog. Fundamentals I: Software / Slide 4

COMP102 Prog. Fundamentals I: Software / Slide 5 l Application software n Easy-to-use programs designed to perform specific tasks l System software n Programs that support the execution and development of other programs n Two major types –Operating systems –Translation systems (compilers & linkers) Software

COMP102 Prog. Fundamentals I: Software / Slide 6 Copyright © 2000 by Brooks/Cole Publishing Company A division of International Thomson Publishing Inc.

COMP102 Prog. Fundamentals I: Software / Slide 7 Computer Software Relationships User Interface Basic Input and Output Services (BIOS) needed for a computer to boot up User InterfaceOperating System User InterfaceApplication Programs Computer Hardware

COMP102 Prog. Fundamentals I: Software / Slide 8 Application Software l Application software makes computer popular and easy to use l Common application software: Microsoft Word, WordPerfect PowerPoint Netscape, Internet Explorer PhotoShop, Photo-Paint Quick Time Dreamweaver

COMP102 Prog. Fundamentals I: Software / Slide 9 l Controls and manages the computing resources l Examples n Windows, Unix, MSDOS, l Important services that an operating system provides: n Security: prevent unauthorized users from accessing the system n Commands to manipulate the file system n Input and output on a variety of devices n Window management Operating System

COMP102 Prog. Fundamentals I: Software / Slide 10 What is a (programming) language? l A program needs to be written in a language l There are many programming languages n Low-level, understandable by a computer n High-level, needs a translator! l C++ is a high level programming language A sequence of instructions A program (in computer language) An algorthm (in human language)

COMP102 Prog. Fundamentals I: Software / Slide 11 l Machine binary language: unintelligible l Low-level assembly language n Mnemonic names for machine operations n Explicit manipulation of memory addresses n Machine-dependent l High-level language n Readable n Machine-independent Levels of programming language

COMP102 Prog. Fundamentals I: Software / Slide 12 Machine binary languageLow-level assemblyHigh-level An example:

COMP102 Prog. Fundamentals I: Software / Slide 13 How to translate? Examples of compilers: n Microsoft Visual C++, Eclipse, g++ A program written in high-level programming language (for example, C++ program) A low-level (machine language) program that is understandable by a computer (for example, a PC) COMPILER (for example, Visual C++)

COMP102 Prog. Fundamentals I: Software / Slide 14 Translation System l Set of programs used to develop software l Types of translators: Compiler Linker l Examples n Microsoft Visual C++, Eclipse, g++

COMP102 Prog. Fundamentals I: Software / Slide 15 Software Development l Major activities Editing (writing the program) Compiling (creates.obj file) Linking with compiled files (creates.exe file) –Object files –Library modules Loading and executing Testing the program

COMP102 Prog. Fundamentals I: Software / Slide 16 Integrated Development Environments l Combine all of the capabilities that a programmer would want while developing software (VC , Eclipse) Editor Compiler Linker Loader Debugger Viewer

COMP102 Prog. Fundamentals I: Software / Slide 17 Our First Program // a simple program #include using namespace std; int main() { cout << "Hello world!" << endl; return 0; } Print statement Ends execution of main() which ends program Comments Function named main() indicates start of program

COMP102 Prog. Fundamentals I: Software / Slide 18 Summary