In this age of computers there is no such activity that cannot be achieved without
computers. computers has become an indispensable ad multipurpose tool. It has
become the need of people just like telephone , television ,mobile phone, or
electronic device.
CONCEPT OF COMPUTERS SYSTEM
A computer is an electronic device or machine. that takes in data & instruction
(input) , works with the data (processing) & brings out information (output).
FULL FORM OF COMPUTER.
C=Common
O=Operating
M=Machine
P=Particularly
U=Used For
T=Technology
E=Education &
R=Research
To know about the working of computer , first need to understand various term such as Data, Processing & Information .first of all ,lets start with three basis terms:-
1. Data :Data is the collection of raw facts and figures without any sequence .When the data is collected as facts and figures, there is no meaning to it ,at that time .
For example :- name of people , names of employees, etc.
2. PROCESSING :Processing is the set of instruction given by the users to the related data that was collected earlier to output meaningful information. The computers does the required processing by making the necessary calculation , comparisons and decisions.
3. INSTRUCTIONS :Instruction are the directives or commands given to the computer according to which it operates the data.
4. INFORMATION:Information is a processed data. It means what we get after processing data (meaningful data) .Data are aggregated and summarized in various meaningful ways to form information.
NOTE:- You should understand that what goes in computers is Data and what comes out of them is Information . This process of turning data into information is also known as Information Processing Cycle.
A COMPUTER IS MADE UP OF THREE MAIN
DEVICE:-
1. Input devices which are used to feed data and instruction to the system.
2. Processing device or Central Processing Unit which process the data according to the instructions.
3. Output
devices which gives out the result of processing to the user.
INPUT DEVICE:-
The computer parts or device which are used to give data and instruction into the computer system are called input devices.
Some Input Device are :-
Keyboard , Mouse , Digital Camera , Drawing Tablet , Microphone , Scanner , Joystick , Touch Screen , Barcode Scanner , Magnetic Ink Character Recognition System (MICR) , Magnetic Strips , Smart Card , Optical Mark Reading (OMR) , Light Pen .
OUTPUT DEVICE:-
Output device are device that we used to get information out of a computer.
Some Output Device are :-Monitor , Printer , Dot Matrix Printer , Inkjet Printer , Laser Printer , Speaker , Plotter , Headphone .
CHARACTERSTICS OF COMPUTER:-
The major characteristics of computers are the following:
1. Speed: A Powerful computer is capable of executing about 3 million calculations per second.
2. Accuracy: Computers can perform all the calculation and comparisons accurately provided the hardware does not malfunction.
3. Reliability: Computers are immune to tiredness and boredom or fatigue. Thus they are more reliable than human beings.
4. Memory/Storage Capacity: We store the data in these types of devices.
5. Versatility: Computers perform repetitive jobs efficiently. They can solve labour problem or hazardous jobs in hostile environment. They even can work in the areas where human brain can error for instance observing motion of very fast moving articles. Also they can work with different types of data and information like graphic ,audio, visual, characters etc.
6. Automation: Once the instructions are fed into computer it works automatically without any human Diligence: A computer will never fail to perform its task due to distraction or laziness.
7. Flexibility: Computers can be used for entertainment, for business, by people who hold different ideals or who have varied goals. Almost anyone can use a computer, and computers can be used to assist with almost any goal.
GOALS OF COMPUTER:-
1. Problem-solving techniques using the computer.
2. Analysis of complex problems and the synthesis of solutions. 3. Comprehension of modern software engineering principles.
3. A vast breadth and depth of knowledge in the discipline of computer science.
COMPUTER CAPABILITIES:-
Like all machines, a computer needs to be directed and controlled in order to perform a task successfully. Until such time as a program is prepared and stored in the computer's memory, the computer 'knows' absolutely nothing, not even how to accept or reject data. Even the most sophisticated computer, no matter how capable it is, must be told what to do. Until the capabilities and the limitations of a computer are recognized, its usefulness cannot be thoroughly understood.
In the first place, it should be recognized that computers are capable of doing repetitive operations. A computer can perform similar operations thousands of times, without becoming bored, tired, or even careless.
Secondly, computers can process information at extremely rapid rates. For example, modern computers can solve certain classes of arithmetic problems millions of times faster than a skilled mathematician. Speeds for performing decision-making operations are comparable to those for arithmetic operations but input-output operations, however, involve mechanical motion and hence require more time. On a typical computer system, cards are read at an average speed of 1000 cards per minute and as many as 1000 lines can be printed at the same rate.
Thirdly, computers may be programmed to calculate answers to whatever level of accuracy is specified by the programmer. In spite of newspaper headlines such as 'Computer Fails', these machines are very accurate and reliable especially when the number of operations they can perform every second is considered. Because they are man-made machines, they sometimes malfunction or break down and have to be repaired. However, in most instances when the computer fails, it is due to human error and is not the fault of the computer at all.
In the fourth place, general-purpose computers can be programmed to solve various types of problems because of their flexibility. One of the most important reasons why computers are so widely use today is that almost every big problem can be solved by solving a number of little problems-one after another.
Finally, a computer, unlike a human being, has no intuition. A person may suddenly find the answer to a problem without working out too many of the details, but a computer can only proceed as it has been programmed to.
HISTORY OF THE DEVELOPMENT OF COMPUTERS:-
In beginning, there were no computers. To add or subtract, man used his fingers and toes. Abacus is known to be the first mechanical calculating device. The main purpose of abacus was that additions and subtraction could be performed quickly. Abacus was developed by the Egyptians in the 10th century B.C, but the final structure was given in the 12th century A.D. by the Chinese educationists. Abacus is made up of a frame in which rods are fitted across with rounds beads sliding on the rod.
NAPIER BONES
Born: 1550 in Merchiston Tower in Edinburgh, Scotland
Napier's Bones in an Abacus invented by John Napier Napier's used the
bone rods for counting purpose where numbers were printed on them. With the
help of these rods, one could do addition, subtraction, multiplication and
division speedly.
NAPIER'S CALCULATOR
Napier's bones is a manually-operated calculating device created by John Napier of Merchiston, Scotland for the calculation of products and quotients of numbers. The method was based on lattice multiplication, and also called rabdology, a word invented by Napier. Napier published his version in 1617.
BLAISE PASCAL
| 19 June 1623 Clermont-Ferrand, Auvergne, France In the year 1642, Blaise Pascal a French scientist invented an adding machine called Pascal's calculator, which represents the position of digit with the help of gears in it. Though these machines were early forerunners to computer engineering, the calculator failed to be a great commercial success. |
PASCAL'S CALCULATOR
Blaise Pascal's 17th-century calculator, the Pascaline, was the first widely used mechanical calculator. While limited to addition and subtraction (multiplication done through repeated addition), it was a marvel.
Geared wheels displayed results, and a clever carry system ensured accuracy. This groundbreaking machine, a testament to human innovation, paved the way for future computers.
LEIBNIZ CALCULATOR
| The stepped reckoner or Leibniz calculator was a mechanical calculator invented by the German mathematician Gottfried Wilhelm Leibniz around 16 and completed in 1694. The name comes from the translation of the German term for its operating mechanism, Staffelwalze, meaning "stepped drum". |
GOTTFRIED WILHELM LEIBNIZ
Gottfried Wilhelm Leibniz was a German polymath active as a mathematician, philosopher, scientist and diplomat who invented calculus in addition to many other branches of mathematics and statistics.
Leibniz was successfully introduced as a calculator onto the market in the year 1646. It was designed further in 1673 but it took until 1694 to complete. The calculator could perform the basic mathematical operations such as add, subtract, multiply, and divide. Wheels were placed at right angles which could be displaced by a special stepping mechanism.
There are five generations of computer are follows:-
FIRST GENERATION OF COMPUTER
The beginning of commercial computer age is from UNIVAC (Universal Automatic Computer).
The first generation computers were used during 1942-1955. They were based on vacuum tubes. Examples of first generation computers are ENIVAC and UNIVAC-1.
ADVANTAGES OF COMPUTER:-
- Vacuum tubes were the only electronic component available during those days.
- Used magnetic drums which provide very less data storage.
- Vacuum tube technology made possible to make electronic digital computers.
- These computers could calculate data in millisecond.
DISADVANTAGES OF COMPUTER:-
- The computers were very large in size.
- They consumed a large amount of energy.
- Non-portable.
- Limited commercial use.
- Very slow speed.
- Used machine language only.
- Used magnetic drums which provide very less data storage.
The second generation computers used transistors. The size of the computers was decreased by replacing vacuum tubes with transistors. The examples of second generation computers are IBM 1400 series and CDC 164 etc.
ADVANTAGES OF COMPUTER:-
- Smaller in size as compared to the first generation computers .
- Used less energy and were not heated. Better speed and could calculate data in microseconds.
- Used faster peripherals like tape drives, magnetic disks, printer etc.
- Used Assembly language instead of Machine language.
DISADVANTAGES OF COMPUTER:-
- Cooling system was required.
- Constant maintenance was required.
- Only used for specific purposes.
- Costly and not versatile.
Third
Generation Computers (1964-1975)
The Third generation computers used the integrated circuits (IC). The first IC was invented and used in 1961. The size of an IC is about 4 square inch. A single IC chip may contain thousands of transistors. The computer became smaller in size, faster, more reliable and less expensive. The examples of third generation computers are IBM 370, IBM System/360, UNIVAC 1108 and UNIVAC AC 9000 etc.
An integrated circuit (IC), sometimes called a chip or microchip, is a semiconductor wafer on which thousands or millions of tiny resistors, capacitors, and transistors are fabricated.
ADVANTAGES OF COMPUTER:-
- Smaller in size as compared to previous generations.
- More reliable.
- Used less energy.
- Better speed and could calculate data in nanoseconds.
DISADVANTAGES OF COMPUTER:-
- Air conditioning was required.
- Highly sophisticated technology required for the manufacturing of IC chips.
The fourth generation computers started with the invention of Microprocessor. The Microprocessor contains thousands of ICs. The LSI (Large Scale Integration) circuit and VLSI (Very Large Scale Integration) circuit was designed. It greatly reduced the size of computer. The size of modern Microprocessors is usually one square inch. It can contain millions of electronic circuits. The examples of fourth generation computers are Apple Macintosh & IBM PC.
ADVANTAGES OF COMPUTER:-
- More powerful and reliable than previous generations.
- Small in size.
- Fast processing power with less power consumption.
- Fan for heat discharging and thus to keep cold.
- Cheapest among all generations.
- All types of High level languages can be used in this type of computers.
DISADVANTAGES OF COMPUTER:-
- The latest technology is required for manufacturing of Microprocessors.
- Limited processing power and speed.
- Memory constraints affecting program size and data processing.
- Relatively high hardware costs.
Fifth Generation
Computers (Present & Beyond)
Scientists are working hard on the 5th generation computers with quite a few breakthroughs. It is based on the technique of Artificial Intelligence (AI). Computers can understand spoken words & imitate human reasoning.
IBM Watson computer is one example that outsmarts Harvard University Students.
TYPES OF COMPUTERS
Computers can be categorized into various types based on their intended purpose and functionality. Here are some common types of computers according to purpose:-
1. Personal Computers (PCs):
- Designed for individual use, typically for general computing tasks such as web browsing, word processing, and multimedia consumption.
- Examples include desktop computers, laptops, and tablets.
2. Workstations:
- High-performance computers optimized for specialized tasks requiring significant computational power, such as graphic design, engineering, and scientific simulations.
- Workstations often feature powerful processors, large amounts of memory, and dedicated graphics processing units (GPUs).
3. Servers:
- Computers designed to provide services or resources to other computers or devices on a network.
- Servers can serve various purposes, including hosting websites, managing databases, and providing file storage and sharing capabilities.
4. Mainframes:
- Large, high-performance computers used primarily by large organizations and enterprises for critical business applications, such as transaction processing, data processing, and resource management.
- Mainframes are known for their reliability, scalability, and ability to handle massive workloads.
5. Supercomputers:
- Extremely powerful computers built to perform complex calculations and simulations at very high speeds.
- Supercomputers are used for tasks such as weather forecasting, scientific research, computational fluid dynamics, and cryptography.
6. Embedded Computers:
- Computers integrated into other devices or systems to perform specific functions.
- Embedded computers are found in a wide range of devices, including smartphones, automotive systems, home appliances, medical devices, and industrial machinery.
7. Gaming Consoles:
- Specialized computers designed primarily for playing video games.
- Gaming consoles typically feature dedicated hardware optimized for gaming performance and may include additional multimedia features.
8. Smartphones and Tablets:
- Mobile devices that combine computing capabilities with communication features, such as making calls, sending messages, and accessing the internet.
- Smartphones and tablets are used for various purposes, including productivity, entertainment, and communication.
9. Wearable Computers:
- Computers integrated into wearable devices, such as smartwatches, fitness trackers, and augmented reality glasses.
- Wearable computers often focus on providing personalized information, health monitoring, and hands-free interaction with digital content.
10.Quantum Computers:
- Cutting-edge computers that use quantum mechanics principles to perform computations using quantum bits (qubits).
- Quantum computers have the potential to solve complex problems more efficiently than classical computers, particularly in fields such as cryptography, optimization, and scientific simulations.
Computers can be generally classified by size and power as follows:-
MICROCOMPUTER
A Microcomputer is a computer that uses a microprocessor as its central processing
unit. Micro-computers are physically smaller in size as compared to mainframe
and mini-computers. Many microcomputers when equipped with a keyboard and screen
for input and output respectively can be used as personal computers (in the
generic sense).
Microcomputers are easier to use and also inexpensive as the
memory used by them i.e. microprocessors and semi conductors have become cheaper
in the last few years. E.g.: The various micro computers widely available are
IBM pcs, APPLE mac etc. the small types of pcs like the palmtop and handheld
are now becoming available.
MINICOMPUTER
It is a
midsize computer. In the past few years the difference between large minicomputers
and small mainframes has decreased significantly just like the distinction
between small minicomputers and workstations.
A minicomputer can support upto
200 users at the same time. E.g. : The various machines widely available are
vax series 8200 and 8300, Honeywell (xps-100), s series 36 level
20,50,60 galaxy-21, hcl-4, nelco-5000 and others.
MAINFRAME
Mainframe
computers known as the Big Iron; are computers that are used
primarily by corporate and governmental organizations. Modern mainframe design
is generally defined by the following features: High reliability and security Extensive
input-output facilities with the ability to offload to separate engines Strict
backward compatibility with older version of software.
SUPERCOMPUTER
Supercomputers are general-purpose computers that function at the highest operational rate or peak performance for computers. Processing power is the main difference between supercomputers and general-purpose computer systems.
Supercomputer is a term used for one of the fastest computers that exist today. They are deployed for specialized applications that require processing of highly critical data and immense amounts of mathematical calculations.
E.g. :- Weather
forecasting requires a supercomputer. PARAM is a series of supercomputers
designed and assembled by the Centre for Development of Advanced Computing
(C-DAC) in Pune, India. The latest machine in the series is the PARAM Yuva II.
China’s vast Tianhe-2 is the fastest supercomputer in the world.
PERSONAL COMPUTERS
Personal Computers are computers that are designed for an individual user. These computers are small and a relatively cheaper. In price, personal computers can range anywhere from a few hundred pounds to over five thousand pounds. Personal Computers use the microprocessor technology as they enable manufacturers to put an entire CPU onto one chip. They serve myriad purposes and can be put to use by various businesses for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. People across the globe use internet for playing games, surfing net and other online applications at their homes and personal use.
Types of Personal Computers:-
Personal computers can be classified on the basis of its size. There are two basic types of the traditional designs i.e. the desktop models and tower models. There are several variations on these two basic types also.
Tower model
This model of personal computer refers to a computer in which the power supply, motherboard, and other mass storage devices are stacked on top of each other in a cabinet.
Desktop model
Desktop model means computer that are designed to fit comfortably on top of a desk, with the monitor sitting on top of the computer. Desktop model computers as compared to the tower model are broad and low, whereas tower model computers are narrow and tall.
Notebook computer
Notebook Computer also called Ultrabook. These are extremely popular because they are extremely lightweight and portable. Because of their small size typically less than 6 pounds or lesser than that, they have become so popular. These flat-panel technologies can produce a lightweight and non-bulky display screen. The quality of notebook display screens also differs considerably. Modern notebook computers are very similar to personal computers in terms of computing power.
Laptop computer
Laptop are now a days also called notebook computers. These are small and portable. You can make them sit on your lap and work on them. Subnotebook computer Subnotebook computers are portable computers that are even lighter and smaller than a full-sized notebook computer. They are light weight because they use a small keyboard and screen as compared to a notebook computer.
Fundamentals of Computer
These computers are portable enough to be carried in one hand. They are extremely convenient for use but due to extremely small size of their keyboards and screens they have still not succeeded in to replacing notebook computers.
Palmtop
These computers as the name suggest fit in your palm. Due to extremely small size their use is limited to phone books and calendars.
PDA
PDA have electronic pens rather than keyboards for inputs unlike laptop. They also incorporate handwriting recognition features, and voice recognition technologies i.e. can also react to voice input. PDAs are also called palmtops, hand-held computers and pocket computers.
Smart phones
Smart phones are cellular phones that function both as a phone and a small pen. They may use a pen or may have a small keyboard. They can be connected to the internet wirelessly. Apple, Samsung, Sony are some manufacturers of smartphones.
