Introduction

We can compare the computer system (Hardware and software) with human and human intelligence respectively. All the activities of human body like running eating, speaking are based on the thoughts and feeling raised by the brain. All these actions are initiated and controlled with our brain. If brain doesn't raise such feeling and control, we will be idle and cannot do anything. similarly computer system (Hardware) is also initiated and controlled with set of programs called software. Programs are the collections of data and instructions in a systematic order to perform some work. These programs are organized and collected in a systematic order to tell the computer what to do and how to do. for example software instruct the hardware what to display on the users screen, what kinds of input to take from the user, and kinds of output to generate.

A set of program, which are specially written to provide the user a precise functioning like solving a specific problems is termed as a software package. for example word processor package helps to create the documents, save document, modify and print the documents. "Software is the collection of program and other associated documents that helps to control, manage and integrate the components of computer system to accomplish a specific task."

Software are broadly divided into two types as:

1. System software
2. Application software

System Software

The software that helps to activate the computer system and provide operating environment for other application software is called system software. It's primary work is to control, integrate and manage the individual hardware components of computer system. This software provides an operating and programming environment where programmer and user can create and the application software for their day to day application. It can be explained into three types:

1. Operating System (OS) : Software that helps to activate the computer system and provide common platform to operate the computer system by the user is called OS. It is the first layer of software loaded into computer memory on the time of booting (Starts Up). The main function of OS is to manage the disk access, files process etc. Other software is loaded on the environment of OS. Windows Xp, Linux, MS-DOS etc are popular OS.
2. Device Drivers: As we discuss, system software helps to activate and recognize the computer hardware devices. To activate and recognize the hardware devices computer system requires special software called device drivers. To work with all devices, we need this software. For example to work with Modem, Printers we have to install their driver software then only these devices will work.
3. Languages Translator: Translator program is a computer program that converts the programming instructions written in human convenient form into machine codes. Computer are digital devices. It can work only on the digits which are 0 to 1. All types of commands, data and instructions required to be converted into machine code which is the combination of 0's and 1's. Different types of programming languages accept the data and instructions on natural language like English. But computer can not process such data and instructions on natural language. So they should be translated into machine code. To convert such natural language. So they should be translated into machine code.

   According to the nature and application processing we have three types of language translators.

   Compilers: Translator systems that compile whole program and translate it into machine code at a time are compilers. This translator translate whole program at a time and creates object code then executive code. E.g.C Program, Pascal etc.

   Interpreters: A translator that can convert the source code (Program code) in line manners without looking at entire program at a time. It translate each statements or lines at a time and translate another line. E.g. Beginners All Purpose Symbolic Instruction Code (BASIC).

   Assemblers: It is a translator that can convert assembly level language into machine code. It is also called source program.

4. Utility Software: System software that increases the performance of the computer system is utility software. It helps to maximize the utilization of devices. E.g. Scan disk, Virus Scanner, disk fragmentation etc.