Basic Computer - History

History of Computer - Before the invention of Computer, Calculator was introduced. Main difference between Calculator and computer is that Computer can do logical operations and calculators can't do logical operations.
ABACUS - Abacus was developed in china in 2600 B.C. by some Chinese people. The Word Abacus means calculating board. This apparatus used a series of moveable beads or rocks. The positions changed to enter a number and again to perform mathematical operations. The abacus, also called a counting frame, is a calculating tool used for performing arithmetic processes. It is made of a beads or stones placed in grooves or strung on rods. Abacus is a Latin word that has its origins in the Greek words abax or abakon (meaning "table" or "tablet").
Leonardo DaVinci was credited with the invention of the world's first mechanical calculator in 1500. In 1642, Balise Pascal invented Adding Machine. Blasie Pascal's supporter think that Mechanical Calculator was introduced by Pascal.
Napier's Bones - John Napier was a methematician who became famous for his invention of logarithms. John Napier built device for the purpose of multipliation in 1617 A.D The device was known as Napier's bones. His bones are set of eleven rods side by side products and quotients of large numbers can be obtained. The sticks were called bones because they were made of bone of ivory.
Charles Babbage was known as Father of computer. He invented Two machines. (i) In 1822, introduced Difference Engine. (ii) In 1834, introduced Analytical Engine. It was first demonstrated in Paris Museum.
First Digital Computer - ENIAC was the first digital computer. The ENIAC was invented by J. Presper Eckert and John Mauchly at the University of Pennsylvania and began construction in1943 and was not completed until 1946. It occupied about 1800 square feet and used about 18000 vacuum tubes a storing device store data, weighing almost 50 tons.
First computer with RAM - MIT introduces the Whirlwind machine March 8, 1955, a revolutionary computer that was the first dil!ital comDuter with magnetic core RAMand real-time graphics.
The first minicomputer - In 1960 Digital Equipment Corporation released its first of many PDP computers the PDP-1.
The first laptop - First Laptop was introduced in 1981 by Adom Osborne and the company "EPSON" manufactured first Laptop.
The first computer company - The first computer company was the Electronic Controls Company and was founded in 1949 by J. Presper Eckert and John Mauchly, the same individuals who helped create the ENIAC computer. The company was later renamed to EMCC or Eckert-Mauchly Computer Corporation and released a series of mainframe computers under the UNIVAC name.
The first multimedia computer - In 1992 Tandy Radio Shack becomes one of the first companies to release a computer based on the MPC standard with its introduction of the M2500 XL/2 and M4020 SX computers.
The first Apple computer - Steve Wozniak designed the first Apple known as the Apple-I computer in 1976.
COMPUTER FUNDAMENTAL
Computer - A computer is a device that accepts information and manipulates it for some result based on a program or sequence of instructions on how the data is to be processed. Computer Le a combination of two words "compute" + "er". Compute means calculation and er means device. In other word Computer is an electronic device. It can perform all type of mathematical and logical operation. It can accept data, store data, process data, retrieve data and print data.
Computer System:- A computer system is a set of components that works together to accomplish one or more task.
Computers are available in different sizes, shapes and weights. Due to different size and shapes they perform different task from one another. They are classified into various category on the basis of physical size, function and processing and storing capacity.
On the basis of physical size, computers are divided into three parts:-
Computer
Desktop
Laptop
Palmtop
1. Desktop:- Acomputer designed for home and personal use. You cannot carry this computer like Laptop. It is a personal computer (PC) Lefor regular use at a single location.
2. Laptop:- A laptop computer is a portable computer and also known as Notebook. One can carry anywhere like briefcase. Another type of laptop is known as Net-book. Netbook is very popular among business man. One can use Net-book for small application like word-processing, accounting, presentation, internet accessing ete.
3. Palmtop:- A small computer that fits on one's palm. Palmtop is also called PDAs,hand help computers and pocket computers.
Another classification of computer, on the basis of function, computers are divided into three parts:-
Computer
Analog
Digital
Hybrid
1. Analog computer:- Analog Machine was introduced by Lord Kelvin. In Analog computers numerical data are represented by measurable physical variables, such as electrical voltage, pressure, temperature etc. A thermometer is a simple analog computer. As the temperature varies, the mercury moves correspondingly.
2. Digital computer:- A computer that accepts and processes data in the form of number (0-9) and characters (A-Z) that has been converted into bmary code. Most computers are digital.
3. Hybrid computer:- The feature of analog and digital machines are combined to create a hybrid computers. You can see hybrid computers in hospitals, geological department etc.
One more classification of computer on the basis of processing speed and storing capacity, computers are divided into four parts. It is also known as types of Digital computer:-
1. Micro computers:- Micro computers known as Personal computers (PC). These are small, relatively inexpensive computers designed for personal use m home or office. It has lowest storing and processing speed. Users can use Micro Computers directly in Home, Office or Public places. Note that user uses micro computer that are digital and also can be laptop or Desktop.
2. Mini computers:- Mini computers are powerful computer as compare to micro computers. It has higher memory, provide faster operating speeds and larger storage capacities than microcomputer and used as server. Minicom uter system known as small mainframe computer system. A mini computer is a multiprocessing system capable of supporting rom 2 to 200 users Simultaneously.
3. Mainframes computers:- A mainframes computer is different from micro and mini. It has very high memory and processing speed and used as server (can support thousands of users). A mainframe is a high-performance computer used for large-scale computing purposes.
4. Super Computers:- Super computer is a different type of computer and can be used for comlex type of application. e.g : scientific research, weather forecasting, weapon designing etc.India's first super computer PARAM-10000 developed by C-DAC, PUNE in 1998, Another super computers are Padam-param (Param series), EKA, SAGA-220 etc. India;s fastest Super Computer is EKA designed by TATA.
Computer of First Generation:
ENIAC:- Electronic Numerical Integrator and Calculator
- It was first general purpose computer.
- Invented by John P.Eckret and John Mauchley in 1946
- Vacuum tube was used as a storage device (18000 V.T)
- Weight was around 70 tons
EDSAC:- Electronic Delay Storage Automatic Calculator
- It was invented by Maurice wilkies in 1949
EDVAC:- Electronic Discrete Variable Automatic Computer (1952)
UNIVAC:- Universal Advance Computer
- It was first commercial purpose computer.
- Invented by John P. Eckret and John Mauchley in 1952
- Vacuum tube was used as a storage device (around 28000 V.T)
Units uses in computers to store and process data:-
Bit :- The full form of Bit is "Binary Digit" or "Binary Integer". A bit is a single digit number in base-2 ('0 or 1') and is the smallest unit of computer data.
4 bit
1 nibble
8 bit
1 byte
1024 byte
1 kilo byte
1024 Kilo byte
1 mega byte
1024 mega byte
1 Giga byte
1024 Giga byte
1 Tera byte
1204 Tera byte
1 Peta byte
1024 Peta byte
1 Exa byte
1024 Exa byte
1 Zetta byte
1024 Zetta byte
1 Yotta byte
CHARACTERISTICS OF COMPUTER
Computers are playing a main role in our everyday life. It solves the human problems very quickly as well as accurately. The important characteristics of a computer are:-
Speed:- Computer is very fast and it takes only few seconds for calculations or you can say the speed of computer in terms of microsecond (10-6 part of a second) or nanosecond [10-9 part of a second).
Accuracy:- The degree of accuracy of computer is very high and every calculation is performed with the same accuracy. The accuracy level is determined on the basis of design of computer. The errors in computer are due to human and inaccurate data. Everything or Result depends on the users input.
Storage Capacity:- A computer has a very large capacity to store information. The Computer has an in-built memory where it can store a large amount of data. To store data in computer, hard disk is used. You can also store data in secondary storage devices such as floppies, which can be kept outside your computer and can be carried to other computers.
Reliability:- Computers are considered to be very reliable machines. The computer respond as the per the instruction keyed into it. They do not make mistakes on their own. Computers error occurs when humans make errors while programming the computers. Reliability is the main key of computer.
Versatility:- It means the capacity to perform completely different type of work. You may use your computer to prepare payroll slips. Next moment you may use it for inventory management or to prepare electric bills.
Diligence:- A computer is free from tiredness. It can work for hours without creating any error. If millions of calculations are to be performed, a computer will perform every calculation with the same accuracy
Applications of a Computer:- Computers have become very popular in all fields. Here are some of areas where they are widely used. Some are given as below:
o Education:- Computers give students more flexibility with their studies. Computers are also used by teachers to prepare lessons, report card and as a reference tool.
o Medicine:- A large number of computerized equipment is used for medical tests in hospitals and clinics. They can be used for storing medical records of patients visiting big hospitals. Doctors can access these records of patients to diagnose.
o Business:- Every company or organization require computers for budgeting, accounting, billing, reporting, presentations etc. This information must be constantly maintained and updated. Computers are also used for sales forecasting, production, planning etc.
o Science and Technology:- Scientist and Engineers use the computers as a tool to experiment, design, and develop their ideas/projects. Architects use computer to design structures. Nuclear test can be simulated without damaging the environment. Computer aided designing (CAD) and Computer aided Engineering (CAE)are becoming very popular.
o Communication:- Today, computer is available in many office and homes and therefore there is a need to share data and programs among various computers with the advancement of data communication facilities. Using Internet facility, you can send E-mail to your friends and relatives.
o Banking:- Computers are being used in banks for carrying out everyday transactions like online enquiry of customers' balance, cheque verification and updating of balance, calculating interests etc. All progressive bank have installed Automated Teller Machines (ATM) to enable the customers to draw money from their accounts, money transfer etc.
o Weather Forecasting:- Data is collected from weather stations and satellites all over the world. Changes in weather and direction of winds can be analyzed with the help of computers. Timely prediction may avoid damage due to natural disasters.
o Entertainment:- Through computers, you can play various games, create your own music, watch cartoons or films, listen to your favorites music etc. Cartoons films are created very easily through computer animation. Special effects like fire, battle earthquake, etc can be created for films.
o Defence:- In defence, computers can be very useful. Modern weapons and missiles are totally computer controlled.
Basic Structure of a computer System:- Computer's follows input → process → output cycle (IPO CYCLE) in order to perform a task. Input means giving data to computers and computer process as per the input, after processing it gives the output.
IPOS CYCLE:- It is how computer intake data , process the data, output information and then saves the information. I stands for input, P stands for processing, 0 stands for output, and S stands for storage.
Input :- Input is the raw data entered into a computer from the input devices. It is the collection of numbers, letters, images, etc. Keyboard, Mouse, scanner, web earn, etc are some examples of the input devices.
Process :- Process is the operation of data or information as per given instruction. It is totally internal process of the computer system. CPU (Central processing Unit) is the main processing device of the computer.
Output :- Output is the result of processed data given by computer after data processing. we can save these results in the storage devices for the future use. Monitor, Printer, Speaker are the main output devices.
The five basic operations that a computer performs are accepting data as a input, processing of data, outputting the information, storage of these data and process control.
ERROR, BUG and DEFECT
Error : it is deviation from logic, syntax or execution. Or programmatically mistake leads to error. A programmer can remove the error from the frogram.
Bug : A fault in a program which cause the program to program in an unintended or unanticipated manner. Or Deviation from the expected result. A QA team or software tester can find the bug. Famous bug-millennium bug. (data Problem) i,e, Y2K Bug
Defect : Mismatch between the requirements. From user point of view it effects the business directly. E.g instantlly halt in the system.
Glitch : A minor malfunction, mishap, or technical problem on computer system known as Glitch.