FOUNDATION IN INFORMATION TECHNOLOGY (CS-T-101) TOPIC : INFORMATION SYSTEM – SOFTWARE

INTRODUCTION A Computer consists of 2 basic parts: Hardware Software

Hardware Physical components of a system

Software Computer instructions or data

Classification of Software System software System software Application software Application software

System Software System software are designed to make the computer easier to use. Example: Operating System

Application Software Application Software is written to enable the computer to solve a specific data processing task. Example: Payroll processing

Utilities Utility programs are those which are very often requested by many application programs. Example: SORT/MERGE

Categories of software packages Database management software Spreadsheet software Word Processing software Graphics software Data Communication software Statistical and Operational Research software

Categories of Languages Machine language Assembly language High level language

Machine Language Sequence of instructions written in the form of binary numbers consisting of 1’s and 0’s for which the computer responds directly. Advantage: It is faster in execution. Disadvantage: It is difficult to understand and develop programs

Assembly Language Employing symbols for the operation part, the address part and other parts of the instruction code. Advantage: It gives more readability than machine Language. Disadvantage: Program is specific to particular machine architecture.

Low Level Languages Machine and Assembly languages are referred to as Low Level Languages.

High Level Language These enables the programmer’s to write programs that are more or less independent of a particular type of a computer. Advantage: Easier to write, read and maintain the programs Examples: COBOL, BASIC, FORTRAN

Compiler A program that takes the entire source code as input and produces as output the object code compiler Source code Object code

Interpreter A program that translates the source code to the object code line by line.

Elements of a programming language Variables, Constants, Array and Expressions Input and Output statements Conditional and Looping statements Subroutine and Functions