Info Orgs.

Parts Of A Computer  and their functions A computer system is made up of hardware and software. Hardware means the physical parts of the computer and software Shears the computer programs that are run on the computer.  The hardware of a computer is classified into three categories -- 1. Input Device  2. Processing Unit, and  3. Output Devices  INPUT DEVICES  : 1. KEYBOARD  The keyboard resembles a typewriter. But there are addmonal keys that handie control functions. The computer keyboard has three categories of keys—~  Alphanumeric keys  Special Keys  Function Keys The Alphanumeric Keys: The Alphanumeric Keys comprise alphabets (A-Z or a-z) ,Numbers (0-9) and other characters like space.  .  /  > < ' " ;  :  ~ @ # $ % ^ & * ( ) + | \ { } [ ] .  The Special Keys : The Special Keys perform specific tasks. Some of the special” keys are Enter or the Return Key, Backspace Key, Del Key, the Ins Key...

 What are the Classification of Computer and their types with  example , function , uses ?  Although a  clear-cut classification of computers is difficult, computers can be broadly classified on the basis of purpose,  components and size.  Purposewise, computers can be classified as - 1. Analog Computers  2. Digital Computers   3. Hybrid Computers   1)  ANALOG COMPUTERS  : Analog computers are computers that are measure physical quantities (e.g. pressure, temperature, length etc} and convert them to numeric values. For example, a thermometer does not perform any calculations but measures the temperature of the body by comparing the relative expansion of mercury.  USES - Analog computers are used mainly for scientific and engineering purposes because they deal with quantities that f vary constantly. They give only approximate results.  Types Of Analog Computer : Slide Rules Differential Analysers Castle Clock Electroni...

Types of Computers and their example with a Brief ( With Picture & Video ) Computers vary widely in performance, size and cost. Depending upon these parameters, the computer industry classifies them into following Categories : :> 1. Microcomputers (Micros, for short)  2. Minicomputers (Minis, for short)   3.  Mainframes  4. Supercomputers  Performance is measured in terms of speed of processing instructions, storage capacity, ability to handle a large number of input and output devices, and nature of operations performed. Generally, better the performance, the larger the size, and higher the cost.  1.  MICROCOMPUTERS  Microcomputers are the lowest end of the computer range. The special purpose devices that are used to control washing machines and the highly visible personal computers you use on desktops both fall under this category.  The most common applications of the PC are word processing, spreadsheet calculating and database ...

Generations Of Computers and their Evolutions  ? FIRST GENERATION OF COMPUTERS (1949-55) :      The first electronic computer was introduced in 1946 by a team led by Professors Eckert and Mauchly at the University of Pennsylvania in U.S.A.-This computer was called Electronic Numerical.integrator and Calculator (ENIAC). It used high speed vacuum tube switching devices. It had a very small memory and  was designed primarily to calculate the trajectories of missiles.  The ENIAC added two digits in around 200 microseconds and multiplied in about 2800 microseconds.   IMPLEMENTATION OF PROGRAM LOOPS : The first computer was designed and commissioned in 1949  at Cambridge University, U.K. under the leadership of Professor Maurice Wilkes. This computer called EDSAC (Electronic Delay storage Automatic Calculator) used mercury delay lines for storage.      Early in the 1950s, stored programme electronic computers saw commercial manu...

How to Compilation and Execution A C programming File Once you have written the program you need to type it and instruct the machine to execute it To type your C program you need another program called Editor. Once the program has been typed it needs to be converted to machine language (Os and Is) before the machine can execute it. To carry out this conversion we need another program called Compiler. Compiler vendors provide an Integrated Development Environment (IDE) which consists of an  Editor as well as the Compiler.   T here are several such IDEs available in the market targeted towards different operating systems. For example, Turbo C, Turbo  C++ and Microsoft C are some of the popular compilers that work under MS-DOS; Visual C++ and Borland C++ are the compilers  that work under Windows, whereas gcc compiler works under Linux. Note that Turbo C++, Microsoft C++ and Borland C++ software also contain a C compiler bundled with them. If you are a beginner you woul...

The Write First Program  in C Language ? Armed with the knowledge about the types of variables, constants & keywords the next logical step is to combine them to form instructions. However, instead of this, we would write our first C program now. Once we have done that we would see in detail the instructions that it made use of.  what are the Common Rules that are applicable to most of the programs languages ? C program rules that are applicable to most of the programs language :  Before we begin with our first C program do remember the following rules that are applicable to all C programs:  (a) Each instruction in a C program is written as a separate statement. Therefore, a complete  C program would comprise a series of statements.  (b)  The statements m a program must appear m the same order in which we wish them to be executed, unless of course the logic of the problem demands a deliberate ‘jump" or transfer of control to & statement, which i...

 The C Language character Set            A Character denotes any alphabet ,digit or special symbol used to represent information . Figure 2 shows the valid alphabets numbers and special symbols allowed in c. Constants, Variables and Keywords  The alphabets, numbers and special symbols when properly combined form constants, variables and keywords. Let us see what are ‘constants’ and ‘variables’ in C. A constant is an entity that doesn’t change, whereas, a variable is an entity that may change.  In any program we typically do lots of calculations. The results of these calculations are stored in computer’s memory. Like human memory, the computer’s memory also consists of millions of cells. The calculated values are stored in these memory cells. To make the retrieval and usage of these values easy these memory cells (also called memory locations) are given names. Since the value stored in each location may change the names given to these loc...