Computer Software

Introduction to Computer Software

For as long as there has been computer hardware, there has also been computer software. But what is software? Software is just instructions written by a programmer which tells the computer what to do. Programmers are also known as 'software developers', or just plain 'developers'.

Nothing much is simple about software. Software programs can have millions of lines of code. If one line doesn't work, the whole program could break! Even the process of starting software goes by many different names in English. Perhaps the most correct technical term is 'execute', as in "the man executed the computer program." Be careful, because the term 'execute' also means (in another context) to put someone to death! Some other common verbs used to start a software program you will hear are 'run', 'launch, and even 'boot' (when the software in question is an operating system).

Software normally has both features and bugs. Hopefully more of the former than the latter! When software has a bug there are a few things that can happen. The program can crash and terminate with a confusing message. This is not good. End users do not like confusing error messages such as:

Site error: the file /home7/businfc6/public_html/blog/wordpress/wp-content/plugins/seo-blog/core.php requires the ionCube PHP Loader ioncube_loader_lin_5.2.so to be installed by the site administrator.

Sometimes when software stops responding you are forced to manually abort the program yourself by pressing some strange combination of keys such as ctrl-alt-delete.

Because of poor usability, documentation, and strange error messages, programming still seems very mysterious to most people. That's too bad, because it can be quite fun and rewarding to write software. To succeed, you just have to take everything in small steps, think very hard, and never give up.

I think everyone studying Information Technology should learn at least one programming language and write at least one program. Why? Programming forces you to think like a computer. This can be very rewarding when dealing with a wide range of IT-related issues from tech support to setting up PPC (pay-per-click) advertising campaigns for a client's web site. Also, as an IT professional, you will be dealing with programmers on a daily basis. Having some understanding of the work they do will help you get along with them better.

Software programs are normally written and compiled for certain hardware platforms. It is very important that the software is compatible with all the components of the computer. For instance, you cannot run software written for a Windows computer on a Macintosh computer or a Linux computer. Actually, you can, but you need to have special emulation software or a virtual machine installed. Even with this special software installed, it is still normally best to run a program on the kind of computer for which it was intended.

There are two basic kinds of software you need to learn about as an IT professional. The first is closed source or proprietary software, which you are not free to modify and improve. An example of this kind of software is Microsoft Windows or Adobe Photoshop. This software model is so popular that some people believe it's the only model there is. But there's a whole other world of software out there.

The other kind of software is called open source software, which is normally free to use and modify (with some restrictions of course). Examples of this type of software include most popular programming languages, operating systems such as Linux, and thousands of applications such as Mozilla Firefox and Open Office.

But what is the real difference between open source and closed source software? Is open source source software just about saving money? Let's investigate. Let's say for instance you find a bug in the latest version of Mozilla Firefox. The bug is causing a major project to fail and you need to fix it right away. This is not very likely to happen, I realize, but it's just an example. You might take the following steps:

Step 1. Download and unzip (or uncompress) the source code from Mozilla.

Step 2. Use an Integrated Development Environment (IDE) and a debugger to find and fix the bug in the source code. Please note that you will need to know a little C++ to debug applications such as this.

Step 3. Test the fix and then use a compiler to turn the source code into a binary file. This can take a long time for big programs. Once the source code is compiled then the program should work!

Step 4. You are almost done. Now send the bug fix back to the Mozilla Firefox team. They may even use your bug fix in the next release!

Now imagine you find a bug in a proprietary code base such as Microsoft Word. What can you do? Not much, just file a bug report and hope someone fixes it at some point.

This is a rather radical example, but I think it illustrates to a large degree why programmers generally prefer open source software to closed source alternatives. Good programmers love code and they want access to it. Hiding the code from a programmer is like hiding the car engine from an auto mechanic. We don't like it!

Now you have learned a little about software. You will learn more about software applications and programming in later units.

computer software

A computer can do various tasks according to our requirement. The working of the computer depends on the software used in it. A computer can solve very complex problems with in a second . The talent of the computer also depends on the software used in it . The software makes the computer such a powerful and multi-functional machine . A computer like a dead body without software. it can do nothings without software.
        A set of instruction that performs specific task in the computer is called a computer program. The collection of of computer program and related data that provide the instruction telling a computer what to do is called a software. In the program ( or software ) a sequence of instruction are written  to preform a specified task for a computer. A computer preform task by following such program instructions. It instructs all the parts of computer system what task it should perform and how.
           The collection of computer program and related data that provide the instruction telling a computer what to do is called a software.
                         Computer hardware can only understand two basic concepts On and Off . The On and Off concept is called binary . Computer software were developed in order to make binary into a useful way to tell the computer hardware what to do. Hardware starts functioning once software loaded . Software is such a part of computer system that you cannot see, feel or touch. Some example of computer software are: Micro soft Windows, MS-Word, MS-Excel, Window Media player, notepad, Adobe Photoshop, etc.

Types of Software:

We various types of software to perform different tasks by using computer. A special type of software, that controls the operation of a computer and devices attached with the computer is called operating system software . The word processing software such as Microsoft Word is used to create and edit documents such as letters, reports, essays, etc. The presentation software such as Microsoft power point. is used to create slides for making presentation game are used to play computer games. The software like Window like Window media player is used watch movie and listen music. Computer software can be broadly categorized into two types. They are :
A. System Software
B. Application Software

A. System Software:
System software is a set of programming that manages and support the computer resources and operations of a computer system. System software are essential to operate a computer . It creates like links between the user and computer as well as provides and maintains a platform for running application software. The system software functions as a bridge between computer system hardware and application and the application software. Without this software no link can be created between the user and computer . An operating system software is a type of system software.

System software is a type of computer program that is designed to run a computer's hardware and application programs.
      Basically a system software performs the following tasks.

Monitoring the use of all hardware components.Communicating  with peripheral devices such as printer, scanners, webcam , card reader, etc.
providing an easy interaction between the user and computers.
Managing the files and folders.
Running the application software.
Development of other types of software.


The system software can sub- divided into four basic types.
1. Operating system software
2. Utility Software
3. Device Driver software:
4. Language processor Software.

1. Operating system software:
An operating system, or OS, is a software program that enables the computer hardware to communicate and operate with the computer software. Without a computer operating system, a computer would be useless. An operating system controls and co-ordinates the overall operations of the computer system. It manages the computer hardware , controls the execution of application program and provides the set of service to the users. An application program cannot access input / output devices or execute programs instruction itself. The operating system performs these task through CPU on behalf of application programs. An operating system is an interface between the user and the computer . The user interact with operating system indirectly through application program refers the request of the user to operating system . With an operating system manages all the operation of the computer and performs basic tasks such as:


It accepts input from input devices and sends the output through output devices.
It manages all other programs that run on the computer and it run s application programs for the user .
It manages all the files an folders on the storage devices  i.e. stores and transfer from one devices to another.
It manages & controls all the hardware devices and co-ordinates them with another programs.
It provides interface to the user to interact with computer i.e. establishes communication channels between computer and the user,
It manages the memory, that is, allocation of the memory space to the running programs.

     Some examples of operating system are: Windows, Dos, Linux, Unix Macintosh operating system ( Mac OS ). etc.

2. Utility software:
The software, which is used to maintenance your computer system is known as utility software . It is a kind of system software that perform special jobs in the computer such as virus clean, format disk, fragmentation disk, etc. These software  are designed to make your computer function smoothly. A single pieces of utility software  is usually called a utilities or computer from tool. Norton antivirus is an example of utility software that protects your computer from viruses.
    Some examples of utility software are: Norton Utilities, Antivirus software , Network utilities , screen saver, File manager, Backup. Disk Defragmenters, Disk storage, Data recover, etc.

3. Device Driver software:
The devices attached with the computer are controlled by the special system software called device drivers. The device driver tells the operating system how to communicate with a peripheral device such as printer, scanner , etc. To communicate with a device , each device has its own device driver software. If you attached a new driver or hardware such as scanner to computer then you to install its driver software. Usually the operating system has the built-in device driver for commonly used for commonly used input/output devices such as mouse, keyboard, pen drive, etc. The operating system automatically installs these driver software. When you boot a computer, the operating system loads each device's driver software. Example:- printer's driver, scanner's driver, webcam's driver, etc.

4. Language processor software :
A computer only understands the machine level language also called binary language i.e. is and OS. So the programmer have to write instructions to the computer using Os and Is. However writing program instructions using Is and Os is very difficult, tedious and time consuming. So people developed other artificial languages to write program instructions. Nowadays such artificial languages. But the program instructions written by using programming languages must be translated into machine level language or machine code by using language processor software.
   A piece of software that translates the programming language into machine code is called language processor software.
      The language processor software can convert the High Level language or Low level language into machine understandable form. there are three types of language processor and they are:
a. Assembler
b. Interpreter
c. Compiler

a. Assembler:
It translatable the program written in assembly language into machine code. The assembler reads each assembly instructions and convert then into machine instruction to machine instructions. The execution of code occurs only when the whole conversion process is finished. If any errors exit in the assembly instructions, they have to be correct and assembled again.
 Assembler is a program which is used to translate assembly language statements into the target computer's machine code. For example : Pseudo Assembly.
b. Interpreter:
An interpreter is a program that translates the program written in high-level language into a machine language. An interpreter translates to machine code, executes the instruction, then translates and executes the next one and so on until the end of the program. That means the interpreter converts one line of code at a time, and then runs it. Therefore, the  initial start up time to the program is almost negligible. If there is any error on the middle of the program then the program is interpreted in between. After removing the error, the program needs to run again from the beginning. The The programming languages like, QBASIC, GWBASIC, BASICA, LOGO, etc are interpreter based languages.

c. Compiler:
The compiler is also a program, which translates the  program written i high-level language into a machine language. In case of compiler, it reads a whole block of code at a time, converts it into excusable machine code, and  the code. Therefore , all errors are limited at the end of compiler if they are found. For the successful compilation, there should not be tiny errors in the program. The initial start up time to run programs more as compared to the interpreter . Once the code is compiled, then the initial start up time to run the program is negligible. In addition, there is no need of re-translation for execution of programs once the compiler translates the programs.
  source code is a program written in a high -level language. When it is translated into machine code is known as compilation.
The program language like: C, C++, Java, P hp, Net, etc are compiler based language.

B. Application software :
Application software is a set of one or more programs, designed to solve a specific problems of the user through computer or do a specific task in the computer or do a specific task in the computer. These software are created specially according to the user's need . For example, an application software for payroll processing produces pay slips as the major output, and an application software for processing examination results produces mark sheet as the major output. The program included in the application software packages is called application programs and the programmers who prepare application software are called application programmers.
 The application software are either created by software companies or by an individual . The ready packages are also available in the market on Cs for various purposes. the user solve their problems by using ready packages more easily and quickly. Some of application software, communication software, etc. Personal assistance software, Education software , entertainment software etc.
The computer system has no specific use without application software.
 Application software may be used for a verity of purpose :
As a business tool.

To assists with graphics and multimedia projects.
To support home, personal and education activities .
To facilitate communication.
As an application aid in the entertainment industry.
Application software is controlled by the system software, which manages hardware devices and performs background task from them.

The application software can be sub-divided into two types:

a. Tailored or customized software:
Tailored software is the software specially designed to meet the specific requirement of an organization or individual. Tailored software is written on the demand of individual need and serve only one user organization. Following are some examples of tailored software:

• SLC result Processing Software
• Tally Accounting Software
• Media-Pro Software
• Billing Software
• School information system etc.

b. General packed software:
The software which is used to preform the specific task is known as packed software. It is user software which is used by many users for the different purposes. It is a ready-made program which is used to solve the specific job.
Following are the example of packed software.

Spreadsheet software:
Spreadsheet software is a numeric data analysis tool that allows you to create a kind of computerized ledger. Lotus 1-2-3, Excel are the best example of spreadsheet software.

Word- processing software:
Word processing is a term that describe the use of computer to create. edit, view, format, store, retrieve and print documents. Word processing software is the software that enables user to do all tasks on the computer system. For example: word star, Word perfect, Ms-Word, Word pad etc.

Database Software:
Database software is a set of one more programs that enables user to create a database, maintain it and organize its data in designed fashion and retrieve useful information from it. For example d Base, For Pro, Fox Base, Ms- Access, Oracle, SQL etc.

Graphic Software:
Graphic software enables us to use a computer system for creating, viewing, storing , retrieving,and printing of designs, drawings, pictures, graphs etc. For example Freehand , Crow draw,Photoshop, etc.