Lesson 2 - Computer Software PDF

Lesson 2 Computer Software Nethmi Weerasingha Department of Data Science Faculty of Computing NSBM Green University Lesson Outline ØIntroduction to Computer Software ØClassification of Computer Software - System Software - Application Software ØFunctions of Operating Systems - Types of Opera...

Lesson 2 Computer Software Nethmi Weerasingha Department of Data Science Faculty of Computing NSBM Green University Lesson Outline ØIntroduction to Computer Software ØClassification of Computer Software - System Software - Application Software ØFunctions of Operating Systems - Types of Operating Systems ØIntroduction to Utility Software - Functions of Utility Software 2  Computer Software Software is a program which consists of a set of instructions that enables a computer to perform a specific task. It tells a computer what tasks to perform and how to perform them. Those instructions are written in a language that can be understood by the computer hardware and it tells the hardware what to do. Hardware would be a brainless body without software. It is intangible. 3 Classification of Computer Software 4 System Software A collection of complex programs which are designed to control and operate the computer system. Act as the interface between the Hardware and Application software. It includes the programs that are mostly used to control computer itself and hardware devices. It provides a platform to other software. Eg: Operating system, Device drivers, Firmware, Utility 5 software Application Software A software which is developed to help the user to perform specific tasks. Acts as a mediator between the End User and System Software. Cannot run on itself but is dependent on system software to execute. Eg: Word Processing , Spreadsheet , Database, Multimedia software, Web browsers etc. 6 7 System Software vs Application Software 8 Examples for Application Software 9 Exercise Find out examples for the following: – Operating system – Device drivers – Utility software – Word Processing software – Spreadsheet software – Database software – Multimedia software – Web browsers 10 Operating System A set of programs that control the execution of application programs and acts as an intermediary between the user and the hardware. It manages the computer hardware as well as provide an environment for application programs to run. Eg: Windows, DOS, Linux, Ubuntu, MacOS etc. 11 Examples for Operating System 12 Functions of an Operating System Process Management OS allows the computer to operate multiple activities (processors) at once. OS allocates all the necessary resources for a process and manage them efficiently. Memory Management OS makes sure that enough computer memory (primary and secondary memory) is allocated for each process operated by the computer. The memory is freed once a process ends. 13 Functions of an Operating System Device Management OS is responsible for the management of all the peripheral devices connected to a computer system. OS checks whether the devices are working properly. File Management OS manages the file system of the computer which allows us to save data in files and folders. OS allows to create, delete, rename etc. of those files and folders. 14 Functions of an Operating System Provide user interfaces OS provides user interfaces to input commands and instructions in a user- friendly manner. Users can perform tasks using these interfaces, without using complex instructions. Security Management Protecting the computer from different kind of attacks is managed by the OS up to some extend. OS uses various kinds of techniques to perform this function. 15 Types of Operating Systems Single-user OS Multi-user OS Multi-tasking OS Real-Time OS 16 Types of Operating Systems Single-user OS – Provides services to one person at a time. Eg: DOS, Windows 3x, Windows 95/97/98 Multi-user OS (Network OS) – Allows multiple users to use a system simultaneously. – Installed in network environments where many users need to share resources such as files, printers in a network setup. Eg: Windows Server OS, Ubuntu Server, Red Hat Enterprise 17 Types of Operating Systems Multi-tasking OS – Allows to run multiple process at the same time. Eg: Microsoft Windows, Macintosh OS Real-Time OS – Install in special purpose embedded systems used in scientific devices and small gadgets such as ATM, Robots, Cars and Modems. – Gives the output in real time without any observable delays. – Specifically designed for some devices. Eg: Microsoft Windows 2000, IBM OS/390 18 Utility Software A set of programs that help the functioning of the computer and system maintenance tasks. Utility software helps in managing the resources of the computer. Many utility programs are available in the Operating System for the functioning of the machine as well as to protect from security threats. 19 Utility Software Eg: Back up software Anti-Virus Software Disk cleanup and management tools Defragmentation tools Compression tools Disk partitioning software Screen savers etc. 20  Functions of Utility Software Copy files and take back up of hard drives (Backup software) Protect the computer by identifying and eliminating malicious software. (Anti-virus software) Check the errors in hard drive (Disk scanner) Organize the hard disk by rearranging scattered files on the drive with clusters of small spaces together and creating a larger free space. (Disk defragmentation) Compression of larger files into smaller files (File compression) Display information regarding the processes and programs in a computer and the general status of the computer (Task manager) 21  Functions of Utility Software Monitor errors in hardware and software of a computer or network of computers and diagnosis of system errors. (System diagnosis tools) Can divide an individual drive into multiple logical drives. (Disk partitioning software) Blanking the screen or filling it with moving images or patterns when the computer is not in use. (Screensavers) Provide detailed information about the software installed and hardware attached to the computer. (System profilers) Analyze the computer's network connectivity, configure network settings, check data transfer or log events. (Network utilities) 22 Exercise Find out examples for the following: – Back up software – Anti-Virus Software – Disk cleanup and management tools – Defragmentation tools – File compression tools – Disk partitioning software – Screen savers 23 Thank You.. 24 Will meet with the 3rdLesson next day… [email protected]