Software

SOFTWARE

A set of instructions that directs a computer's hardware to perform a task is called a program, or software program. Software comprises the entire set of programs, procedures, and routines associated with the operation of a computer system. The two main types of software are system software and application software.

System software controls a computer's internal functioning, chiefly through an operating system , and also controls such peripherals as monitors, printers, and storage devices. Utilities and compilers are also parts of system software.

Application software, by contrast, directs the computer to execute commands given by the user and may be said to include any program that processes data for a user. Application software thus includes word processors, spreadsheets, database management, inventory and payroll programs, and many other "applications." They can be of three main types:

1. Office Suites

2. Graphic Applications

3. Communication Applications

SYSTEM SOFTWARE

Operating System:

The operating system is a remarkably complex set of instructions that schedules the series of jobs (user applications) to be performed by the computer and allocates them to the various hardware systems of a computer, such as the central processing unit, main memory, and peripheral systems. It is the master program based on which all other program work. Popular operating systems are Microsoft Desk Operating System (MS-DOS), Microsoft Windows, Red Hat Linux, Apple Mackintosh, etc.

MS-DOS: Released in 1981, MS-DOS is a command-line operating system which requires the user to enter all commands from a command prompt. It performs two types of functions:

1. Automatic functions which read data, allocate memory units and control peripheral devices.

2. Command functions which are carried out as instructed by the user.

Microsoft Windows: Windows is a graphical command program, the third version of which was released in 1990, gained immense popularity. By 1993, Windows 3.0 and its subsequent versions were selling at a rate of one million copies per month, and nearly 90 percent of the world's PCs ran on a Microsoft operating system. In the same year Microsoft released Windows NT, a landmark program that tied disparate PCs together and offered improved reliability and network security. By 1996 Windows NT was hailed as the likely standard for PC networking. In 1995, the Microsoft released Windows 95, which fully integrated MS-DOS with Windows and also the revolutionary Internet Explorer. Windows 95 was followed by Windows 98 and Windows 2000. The latest version of Windows, Windows XP was released in November, 2001.

Linux: Linux, seen as the major threat to Microsoft’s superiority in the software arena, was created by Linus Torvalds in 1991. Unlike Windows, Linux can be modified by anyone who knows programming to suit their purposes as its source code is available to users. It is also inexpensive when compared to Windows. Red Hat Linux is a popular version of the operating system.

Utilities: Utilities are accessories which help the Operating System to perform tasks. Built-in utilities of Windows can be accessed from Start > Programs > Accessories > System Tools. Disk Cleanup scans the hard disk for unnecessary program files that can be safely deleted. This saves disk space. Scandisk checks the data written into the hard disk for errors and automatically repairs them. Disk Defragmenter groups files together, which helps to speed up the PC’s performance. Add-on utilities like Direct X, Norton Utilities, etc are also available which help to keep the machine in condition. Hardware drivers are also utilities.

Compilers and Linkers: Compilers are programs which convert programs written in high-level languages into machine language and vice versa. A linker links various compiled modules of a program and includes the required OS environment routines so that the program is complete. All high-level languages come with compilers and linkers.

APPLICATION SOFTWARE

Office Suites:

An office suite is a collection of software designed to perform tasks related with the documentation official papers. It contains applications that can prepare letters, memos, reports, presentations, spreadsheets, databases, and web pages. Some popular office suites are Microsoft Office, Lotus SmartSuite, Sun Star Office, etc.

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