Introduction To Computer What is a Science o

Introduction To Computer

What is a Science? o o o Science is "knowledge attained through study or practice" Knowledge covers general truths of the operation of general laws, esp. as obtained and tested through scientific method [and] concerned with the physical world. " Refers to a system of acquiring knowledge. This system uses observation and experimentation to describe and explain natural phenomena.

What is Technology? o Practical application of science is technology. o Technology is a human innovation in action that involves the generation of knowledge and processes to develop systems that solve problems. ?

Data and Information o What is data? Data is unorganised facts, numbers, letters and symbols represented in a formalised manner suitable for communication, interpretation and processing by humans or computers. o What is information? Information is data which has been assigned a commonly understood meaning.

Data AB 34652 22025 46723 45890 98345 ? ?

Information Number of Products Sold in November in All Sales Areas Product South AB 34652 22025 North 46723 East 45890 West 98345

Information Technology o o Information technology refers to both the hardware and software that are used to store, retrieve, and manipulate information. The practice of creating and/or studying computer systems and applications.

Communication o The term 'Communication' has been derived from the Latin word 'communis' that means 'common'. Thus 'to communicate' means 'to make common' or 'to make known'. This act of making common and known is carried out through exchange of thoughts, ideas or the like. o Communication is a process of transferring information from one entity to another.

E-World o o o e. World stands for electronic world, is responsible for providing online services. It includes email (e. Mail Center), news, and a bulletin board system (Community Center). Users of e. World are referred to as "e. People".

E-World Email: o Messages automatically passed from one computer user to another, often through computer networks and/or via modems over telephone lines. Bulletin Board System (Community Center) o A computer and associated software which typically provides an electronic message database where people can log in and leave messages. Messages are typically split into topic groups. Any user may submit or read any message in these public areas.

What is a Computer? o An electronic device that can perform the following tasks: n n n Respond predictably to input Store the set of instructions needed to process the input Process the input according to these instructions Store the results of processing Output information ?

How is a computer defined? Electronic device operating under the control of instructions stored in its own memory Accepts data Raw facts, figures, and symbols Processes data into information Data that is organized, meaningful, and useful Produces and stores results

How computer works: All computers take in information called input and give out information called output

Components of a Computing System Input Processing Output Storage

Four Hardware Components Input device sends data to the central processing unit Central processing unit (CPU) holds data and programs temporarily and executes computer instructions Output device makes processed data (information) available Secondary storage device stores data and programs

HISTORY OF COMPUTER Calculating Machines o o o The first calculating device called ABACUS was developed by the Egyptian and Chinese people. Its only value is that it aids the memory of the human performing the calculation. A skilled abacus operator can work on addition and subtraction problems at the speed of a person equipped with a hand calculator Abacus Computer 16

HISTORY OF COMPUTER Napier’s bones o o English mathematician John Napier built a mechanical device for the purpose of multiplication. He invented logarithms, which are a technology that allows multiplication to be performed via addition. The magic ingredient is the logarithm of each operand, which was originally obtained from a printed table. Napier also invented an alternative to tables, where the logarithm values were carved on ivory sticks which are now called Napier's Bones. 17

HISTORY OF COMPUTER Slide Rule o English mathematician Edmund Gunter developed the slide rule. This machine could perform operations like addition, subtraction, multiplication, and division. It was widely used in Europe in 16 th century. 18

HISTORY OF COMPUTER Pascal's Machine o o Pascal invented the Pascaline as an aid for his father who was a tax collector. Pascal built 50 of this gear-driven onefunction calculator (it could only add). A machine consisted of wheels, gears and cylinders, that could add and subtract. 19

HISTORY OF COMPUTER Leibniz’s Multiplication and Dividing Machine q It could both multiply and divide. q German co-inventor managed to build a four-function (addition, subtraction, multiplication, and division) calculator that he called the stepped reckoner. q It employed fluted drums having ten flutes arranged around their circumference in a stair-step fashion. 20

Babbage’s Analytical Engine Charles Babbage (father of computer) built a mechanical machine to do complex mathematical calculations. Mechanical and Electrical Calculator Mechanical calculator was developed to perform all sorts of mathematical calculations. Later mechanical calculator was developed to the electrical calculator. Modern Electronic Calculator o o o At first made quite bulky then transistors. It can do all kinds of mathematical computations and store some data permanently. Its size is too small. 21

Types Of Computers o 1. 2. 3. Computers Can be divided into the following types on the basis of their working: Analog Computers Digital Computers Hybrid Computers

Types Of Computers o Analog Computers: o An analog Computer does not operate with digital signals. It recognizes data as a continuous measurement of a physical property. it has no state. Analog computer is difficult to operate and use. Voltage , pressure, speed and temperature are some physical properties that can be measured in this way. Analog computer is mainly used in the field of engineering and medicine. o

Types Of Computers o 1. 2. Examples: The speed of the car is measured by speedometer Analog clock measures time by the distance of the hands of a clock around a dial.

Types Of Computers o Digital Computers: o A Digital Computer Works with Digits. Everything Is described in two states i. e. either on or off. The number 1 represents on and 0 represents off state. it operates by counting numbers or digits and gives output in digital form. The digital computers are very fast. These computers store result in digital form. o

Types Of Computers o 1. 2. Examples: Digital watch is a good example of digital computer. Score board that directly count discrete values such as the time left to play and the score of each team.

Types Of Computers o Hybrid Computers: o These types of computers are, as the name suggests, a combination of both Analog and Digital computers. A hybrid computer combines the best characteristics of both the analog and digital computer. It can accept data in analog and digital form. Examples: Hybrid computer devices may calculate patient’s heart function , temperature, blood pressure etc. o o

o Categories of Computers

Categories of Computers Personal Computers (desktop) Mobile Computers and Mobile Devices Midrange Servers Mainframes Supercomputers Embedded Computers Next

Personal Computers n n Designed so all of the components fit entirely on or under a desk or table Refer to a type of computer system that was designed for use by a single person Next

Mobile Computers and Mobile Devices o What is a notebook computer? n n n Portable, small enough to fit on your lap Also called a laptop computer Generally more expensive than a desktop computer Next

Mobile Computers and Mobile Devices o What is a Tablet PC? n Resembles a letter-sized slate Allows you to write on the screen using a digital pen Especially useful for taking notes Offer all the functionality of a notebook PC, but they are lighter. Can accept input from an electronic pen or the user’s voice. n n Next

Mobile Computers and Mobile Devices o What are mobile devices? Ø Small enough to carry in a pocket Ø Internet-enabled telephone is a “smart phone” Next

Mobile Computers and Mobile Devices o o What is a handheld computer? Also called palmtop computers. Small enough to fit in one hand Used by mobile employees such as meter readers Next

Mobile Computers and Mobile Devices o n What is a personal digital assistant (PDA)? Provides personal organizer functions o o o Calendar Appointment book Address book Calculator Notepad Next

Mobile Computers and Mobile Devices o What are smart phones and smart watches? A smart phone is an Internet-enabled telephone that usually provides PDA capabilities A smart watch is an Internet-enabled watch that automatically adjusts to time zone changes and stores personal information Next

Servers o What types of servers are there? Midrange server Powerful, large computer that supports up to a few thousand computers Mainframe Very powerful, expensive computer that supports thousands of computers. Supercomputer The fastest, most powerful, most expensive computer. Used for applications requiring complex mathematical calculations like weather forecasting etc Next

Embedded Computers o What is an embedded computer? n A special-purpose computer that functions as a component in a larger product Next

Capabilities Of Computers have some significant characteristics because of which they are becoming versatile day by day. They have several capabilities and some limitations.

Capabilities Of Computers ( Cont ) Following are some important characteristics of Computers : o Speed o Storage Capacity o Processing o Accuracy o Recalling

Capabilities Of Computers ( Cont ) o o o Control sequence Consistency Communication Versatility Cost Reduction

Description: Speed

Processing A computer can process the given instructions. It can perform different types of processing like addition, subtraction, multiplication and division. It can also perform logical Functions like comparing two numbers to decide which one is greater. Accuracy means to provide result without any error. Computer can process large amount of data and generate error free results.

Recalling A computer can recall the stored data and information as and when required. The data stored in the computer can be used at a later time. The computer can recall the data within few seconds. Control Sequence A computer works strictly according to the given instructions. It follows the same sequence of instructions that is given to a Program.

Consistency Computers works in consistent way. It does not lose concentration due to heavy work. It does not become tired or bore. Computer performs all the jobs with equal attention. Communication Most computers have the capability to communicate with other computers. We can connect two or more computers by Communicating device such as modem. These computers can share data , instructions and information.

Versatile A computer can perform different types of tasks. We can use computers in hospitals , banks or at home. A variety of facilities are available through computers. Cost Reduction By using computers we can perform a difficult task in less time and less cost. For example we may have to hire many persons to handled an office. The same work can be performed by a single person with the help of computer. It reduce the cost.

Limitations Of Computers We have understood the importance of computer in our lives. Does that means that a computer act like an Obedient assistant who can perform all tasks repeatedly at high speed without any error? Lack of Commonsense Yes to some extent computer acts as human being. But there is big difference between the machine and master. A computer is only a tool. It cannot think. It does not have Intelligence or commonsense as well.

Limitations Of Computers (Cont ) Inability to correct When we instruction to the computer we must give the correct instructions. A computer cannot correct the wrong instruction itself. This follows the fact that computer cannot use its brain because it does not have one! Dependence on human instructions A computer cannot generate any information on its own. It can only do what it is told to do.