Computer Software represents the set of programs that govern the operation of a computer system and make the hardware run.
Software can be classified broadly into three categories:
- System Software
- Application Software
1. System Software: A computer is mere a machine that knows nothing of itself. Rather it requires instructions for each and everything it performs. These instructions are provided to it through software. The software that controls internal computer operations (viz. Reading data from input devices, transmitting processed information to the output devices, checking system components, converting data/instructions to computer understandable form etc.) is known as system software.
The system software are categories into two parts:
- Operating System
- Language Processors
Operating System: hardware is nothing but finely designed machinery. A machine is ultimately a machine only, which is always made to work. In case of computers, it is either us if we do that or ‘some other’ which does it for us. This ‘some other’ is nothing but our very own ‘operating system’.
An operating system is a program which acts as an interface between a user and the hardware (i.e., all computer resources).
Operating system is just like our secretary. As the boss given orders to his secretary and the secretary does all the work for his boss. The secretary himself decides : ‘how to do’ ‘what to do’ ‘when to do’, etc.etc. Same ways, we pass our order/request to operating systems and ‘the operating system’ does it for us. ‘operating system’ itself decides: ‘how to do’, ‘what to do’, ‘when to do’? The primary goal of an operating system is thus to make the computer system convenient to use and secondary goal is to use computer hardware is an efficient manner.
An operating system is an important component of a computer system which controls all other components of the computer system. Major components of a computer system are:
- The Hardware
- The Operating System
- The Application Program Routines (compiler, linker, database management system, utility programs)
- The Humanware (users)
2. Language Processors: As programmers prefer to writer their programs in one of the high level language because it is much easier to code in such languages. However, the computer does not understand any language other than its own machine language (binary language) therefore, it becomes necessary to process a high level language program so as to make it understandable to the computer. The system programs which performs this very jobs are language processors. The language processors are Assembler, Interpreter, compiler.
3. Application Software: An application software is set of programs necessary to carry out operations for a specified application. These are the programs written by programmers to enable computer to perform a specific task such as processing words, inventory control, handling calculations and figures, medical accounting, financial accounting, result preparation, railways reservation, billing etc.
Application Software can further be subdivided into three categories:
- Customized Software