Software: Advance Certificate In Information Technology

Software

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Advance Certificate in Information Technology

What is software A

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computer cannot do anything on its own.  It must be instructed to do a desired job.  Hence its necessary to specify a sequence of instructions that a computer must perform to solve a problem.  Such a sequence of instruction written in a language that can be understood by a computer called a computer program.  The set of computer programs, procedures, and associated documents (flowcharts, manuals etc..) that describe the programs and how they are to be used called “SOFTWARE”.

Relationship between hardware and software  In

order for a computer to produce useful output, the hardware and software must work together.  The same hardware can be loaded with different software to make a computer system perform different types of jobs.  Except for upgrade, hardware is normally a one-time expense, where as software is a continuing expense.

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Relationship between hardware and software Users Other System Software and application Operating System Computer Hardware

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Types of software  Software

can be divided into two categories:

System software  Application software 

Software Application Software

Horizontal Applications

System Software

Vertical Applications

System Software  System

software is a set of one or more programs designed to control the operation and extend the processing capability of a computer system.  Four kind of system software programs include: Operating systems.  Utilities  Device drivers.  Language translators 

Operating Systems  Operating

Systems are programs that coordinate computer resources, provide an interface between users and the computer, and run applications.  Functions of OS includes: Managing resources.  Provide user interface.  Running application. 

Operating Systems  Four

basic categories of OS.

Embedded OS :- are used for handheld computers and smaller devices such as PDAs.  Network OS:- (NOS) are used to control and coordinate computers that are linked together.  Stand alone OS:- also called desktop OS, control a single desktop or notebook computers.  Client OS:- is desktop OS that is concerned to, or share a NOS and includes programs on a computer to help organize a great amount of data. 

Example of Operating Systems  MAC

OS

Design to run Macintosh computers.  Market share is less compare to windows.  Powerful and easy to use.  Unique features in Mac Os 

Aqua is intuitive user interface.  Dock provides a flexible  Sherlock locates information on the web as well as on the user’s computer system. 

Example of Operating Systems  MS-DOS 

MS-DOS was the first popular OS for the IBM PC. It employs a command line interface.

Example of Operating Systems  Windows     

Most popular microcomputer OS today is MS Windows. Windows is designed to run with Intel and Intel compatible microprocessors such as Pentium IV. Comes in variety of different versions. Windows provide GUI called desktop. Windows use icons, small graphical representations of programs to aid in navigating the OS

Windows XP

Example of Operating Systems  Unix

and Linux

Unix OS was originally designed to run on computers on network environment.  It is also used by powerful microprocessors and by servers on the web  Linux is free and available from many sources. (encourage further development)  Linux Torvalds developed Linux in 1991 

Operating System Services Program Execution:- system capability to load a program into memory and to run it.  I/O operations:- since user programs cannot execute I/O operations directly, the OS must provide some means to perform I/O.  File system manipulation:- program capability to read, write, create, and delete files  Communications:- exchange of information between processes executing either on the same computer or different systems tied together by a network.  Error detection:- ensure correct computing by detecting errors in the CPU and memory hardware, in I/O devices, or in user programs. 

Utility programs Utility programs are a set of programs that help users in system maintenance tasks and in performing tasks of routing nature.  Some of the tasks commonly performed by utility programs include the following:  Formatting hard disks  Reorganizing files on a hard disk to converse storage space.  Taking backup of files stored on hard disk on to an external storage device.  Search a particular file from directory of thousands of files.  Checking the amount of available memory.  Checking the amount of available storage space on hard disk.  Reducing the file size for efficient transmission over a data communication link. 

Windows Utilities  Windows

programs.

OS are accompanied with several utility

Backup is a utility program that makes a copy of selected or all files that have been saved onto a disk.  Disk Cleanup is a troubleshooting utility that identifies and eliminates nonessential files.  Disk Defragmenter is a utility program that locates and eliminates unnecessary fragments and rearranges files and unused disk space to optimize operation. 

Device Drivers drivers are specialized programs that allows devices such as a mouse or keyboard to communicate with the rest of the computer system.  Whenever a new device is added to a computer system, a new device driver must be installed before the device can be used.  If a particular device driver is not included, the product manufacture will supply one.  Sometimes drivers are available directly from the manufacture’s web site.  Device

Language Translators  Computer

can only understand a language consisting of 0’s and 1’s called machine language.  Language Translators convert human oriented programming languages to machine language.  These translators are indispensable tool for developing new software application and for maintaining existing applications.  Compilers: compiles the whole program at once.  Interpreter: executes one statement at a time.

Application Software  The

term applications software refers generally to all the program that enable computer users to apply computer to the work they do.  You startup all application software through your operating system (system software).  Application programs fall into two categories. Horizontal Applications.  Vertical Applications. 

Horizontal Applications  Horizontal

Applications are used across the functional divisions of a company.  The most popular horizontal applications are called Personal Productivity Programs  They are general purpose programs that address the needs of many people, such as:     

Writing (word processing) Working with numbers (Spreadsheets) Keeping track of information (databases) Prepare presentations (Power Point) Communication (Internet Explorer)

Vertical Applications  Vertical

applications are designed for a particular line of business or a division in a company.  For example: programs are available to handle the billing needs of medical officer, manage restaurants.  Vertical applications designed for professional and business use may cost much more than horizontal applications.

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