SSC

  Introduction to Computer   A computer is an electronic machine that accepts data from the user, processes the data by performing calculations and operations on it and generates the desired output as a result. The term computer is derived from the Latin word 'computare' which means 'to compute'.   Generally, computer is the combination of Hardware and Software which converts data into information. Computer operates on set of instructions only, they cannot think as human being. Computer has an ability to store and execute set of instructions called program which makes it extremely distinguishable and versatile than calculators. Computer makes people's lives easier and more comfortable.    Functioning of a Computer Computer Performs four basic functions -which are as follows

Input Information or data that is entered into a computer is more...

  Computer Architecture   Computer architecture deals with the functional behaviour of a computer system as viewed by a programmer. It can also be described as the logical structure of the system unit that housed electronic components. The computer architecture forms the backbone for building successful computer systems.     Components of Computer A computer consists of following main components

Input/Output (I/O) Unit

Central Processing Unit

Memory Unit

  Input Unit The computer accepts coded information through input unit by the user. It is a device that is used to give required information to the computer, e.g. keyboard, mouse, etc. An input unit performs the following functions (i) It accepts the instructions and data from the user. (ii) It converts these instructions and data in computer in acceptable format. (iii) It supplies the converted instructions and data to more...

  Computer Hardware   Computer hardware refers to the physical components of a computer that can be seen and touched by the user. By the use of these hardware devices, it made very easy for the computer for processing its data, store and retrieve. Hardware is one of the basic and necessary part of a computer system. Computer hardware also includes communication bus, ports, input devices, output devices, etc.   Input Devices An input device can be defined as an electro mechanical device that allows the user to feed data into the computer for analysis and storage and to give commands to the computer. The data is entered into the main memory through the input devices. They accept instructions from the user and convert the accepted instructions into the machine language. Some of the commonly used input devices are described below   Keyboard more...

  Computer Memory   The computer memory is one of the most important elements in a computer system. It stores data and instructions required during the processing of data and output results. Storage may be required for a limited period of time, instantly or for an extended period of time. It also relates to many devices that are responsible for storing data on a temporary or a permanent basis.   Memory Hierarchy The hierarchical arrangement of storage in current computer architectures is called the memory hierarchy. The computer uses a hierarchy of memory that is organised in a manner to enable the fastest speed and largest capacity of memory as shown in figure. Parameters of Memory                Some related parameters of memory are as follow                           (i) Storage Capacity It is representative of more...

  Data Representation   Data representation refers those methods which are used internally to represent information stored in a computer. Computers store lots of different types of information as numbers, text, graphics, sounds, etc.   Number System It defines a set of values that is used to represent quantity. Digital computers internally use the binary number system to represent data and perform arithmetic calculations.   Types of Number System The number systems generally used by a computer are as follows   Binary Number System This system is very efficient for computers, but not for humans. It contains only two unique digits 0's and 1's. It is also known as Base 2 system. The binary numbers 0 and 1 are called a bit. The computer always calculates input in binary form. e.g. (10101 )2 Here, 2 represents base of binary number. more...

  Computer Software   Software is a collection of computer programs and related data that provide the instructions for telling a computer what to do and how to do. A software is a interface between the user and the computer. It is a set of instructions, programs that are used to give command to the hardware. It is responsible for controlling, integrating and managing the hardware components of a computer system and for accomplishing specific tasks.   Types of Software Software can be divided into two major categories

System software

Application software

    System Software It consists of several programs, which are directly responsible for controlling, integrating and managing the individual hardware components of a computer system. System software also provides the interface between the more...

  Operating System   An operating system consists of a set of programs, which controls, coordinates and supervises the activities of the various components of a computer system. It is a program which acts as an interface between the user and the hardware. The interface enables a user to utilise hardware resources very efficiently. Operating system (OS) is an organised collection or intergrated set of specialised programs that controls the overall operations of a computer. It is a program that must be on any computer for proper booting.   Functions of Operating System Operating system is a large and complex software consisting of several components. It is responsible for managing all the resources attached to a computer system. Following functions are provided by an operating system to the convenience of users   Process Management ‘A Process is a program under execution'. It is the more...

  Programming Concepts   It is the sequence of instructions in which the problems of computer tasks and steps are performed with the help of computer. A person who writes or performs the program is known as programmer. Programmer uses some specific languages to write program which is known as programming languages e.g. C++, Java, etc.   Programming Language It is a set of keywords, symbols and a system of rules for constructing statements by which humans can communicate instructions to be executed by a computer. Programming languages are mainly categorised into three parts which are as follows   Low Level Language These programming languages are more arcane and difficult to understand. It is designed to operate and handle the entire instruction set of a computer system directly which are generally used to write the system software, e.g. Machine language more...

  Microsoft Windows   Microsoft Windows stands for 'Microsoft- Wide Interactive Network Development for Office Work Solution.' Microsoft Windows is a series of graphical interface operating system developed, marked and sold by Microsoft. It enables you to work with a wide variety of programs on your computer, often simultaneously.   Versions of MS-Windows Some important versions of MS-Windows are as follows   Windows NT (New Technology) A version of Windows introduced in July, 1993 and made specifically for businesses offering better control over workstation capabilities to help network administrators.   Features

• It is based on High Level Language.
• It is able to run on DOS, Windows 3 and Win 32 applications.
• It has a 32-bit Windows applications.
• It uses preemptive multitasking.
• It provides higher stability and security.

  Windows 95 It is a graphical user interface more...

  Microsoft Office   Microsoft Office was developed by Microsoft Inc in 1988. It is a collection of software’s, based on specific purpose and mainly used in office work. You can start any software of MS-Office by using the Start button.   There are five packages of MS-Office

MS-Word (Word Processing Software)

MS-Excel (Tabular Data Formatting Software)

MS-PowerPoint (Presentation Software)

MS-Access (Database Management Software)

MS-Outlook (E-mail Client)

  Microsoft Word MS-Word is a Word processing application which is one of the most important and widely used applications found on computer. Word processing software is mainly used to the creation of text based documents. It provides tools for composing, editing, formatting and printing of documents smaller than 45 Kb. The document can be a poster, report, letter, brochure. Web page, newsletter, etc. e.g. WordStar, Easy Word, Notepad for Windows.   Start more...