computer science by Firoz rathore,IIT Jodhpur

Category: Education

Presentation Description

this ppt is basically about the different generation of computers, Functional components of computer,hardware and softwares,evolution of computers,types of computers viz. digital computers, analog computers and hybrid computers.


Presentation Transcript

Computer-science project work:

By firoz rathor XI-A Computer-science project work

Computer overview chapter-1:

Computer overview chapter-1


Computer COMPUTER stands for “ C ommon O perating M achine P articularly U sed for T echnical, E ntertainment and R esearch. ” It is particularly an electronic device that can perform a variety of operations in accordance with a set of instructions called program.

Functional components of computer:

Functional components of computer Input unit CPU-Central Processing Unit Arithmetic logic unit Control unit Output unit Memory

Input Unit :

Input Unit An input unit takes the input and converts it into binary form so that it can be understood by the computer. An Input unit is formed by input devices i.e., keyboard, microphone, OMR.

CPU-Central Processing Unit :

CPU-Central P rocessing U nit 1.Arithmetic logic unit(ALU)- The ALU performs all the four arithmetical(+,-,*,/) and some logical(<,>,=,<=,>=,<>) operations .When operations between two or more than two numbers is to be taken place, these numbers are sent to ALU where the operation takes place and the result is put back in the memory. 2.Central Unit(CU)- The CU controls and guides the interpretation, flow and manipulation of all data and Information. The CU sends control signals until the required operations are done properly by ALU and memory.

Output unit:

An output unit converts binary signals Into human understandable language and gives useful output in the form of characters, graphical or audio visual. An output unit is formed by output devices i.e., monitor, speaker, printer etc. Output unit

Memory :

Memory Memory is the electronic holding place for instructions and data that a computer's microprocessor can reach quickly. When a computer is in normal operation, its memory usually contains the main parts of the operating system and some or all of the application programs and related data that are being used. A computer memory has two parts :- 1.RAM 2.ROM

Hardware and software:

Hardware and software


HARDWARE Hardware represents the physical and tangible components of the computer i.e., the components that can be seen and touched. All the electronic, electrical and mechanical equipment that makes up a computer are different hardware. For example:-input devices, output devices, floppy disk etc. Peripherals are also the part of hardware and constitutes the devices that surrounds the system.


software Software represents the set of programs that govern the operation of a computer system and make the hardware run. Software can be classified into three categories:- Operating system An operating system is a program which acts as an interface between a user and the hardware. Language processors language processors is the system program that converts HLL and assembly language into machine language. It has three parts :-assembler, interpreter and compiler. Application software An application software is the set of programs necessary to carry out operations for a specified application. It is divided into two types:- 1.Customised application software 2.General application software

Firmware- like hardware and software, firmware is another term commonly used. Firmware is a prewritten program that is permanently stored in ROM. Liveware- it is the term generally used for the people associated with and benefited from the computer system. :

Firmware- like hardware and software, firmware is another term commonly used. Firmware is a prewritten program that is permanently stored in ROM. Liveware- it is the term generally used for the people associated with and benefited from the computer system.

Strength of a computer :

Strength of a computer 1.Speed a computer can perform a task in a minute that take days if performed manually. A modern computer can execute millions of instructions in one second. 2.High storage capacity computer can store a large amount of information in very small space. 3.Accuracy computers can perform all the calculations and comparisons accurately provided the hardware does not malfunction. 4.Reliability computers are immune to tiredness and boredom or fatigue. 5.Versatility computers can performs repetitive jobs efficiently. They can solve labour problems or do hazardous jobs in hostile environment.

Weakness of a computer:

Weakness of a computer 1.Lack of decision making power computers cannot decide on their own. They do not possess this power which is a great asset of human being , 2.IQ zero computers are dumb machines with zero IQ. They need to be told each and every step, however minute it may be.

Evolution of computer:

Evolution of computer

Abacus :

Abacus Abacus is a bead-and-wire counting machine formed by Mesopotamians. An abacus consists of beads divided into two parts which are movable on the rods of the two parts. addition, subtraction and multiplication of two numbers can be done by using abacus.

Napier’s ‘logs’ and ‘bones’:

Napier’s ‘logs’ and ‘bones’ Napier's bones is an abacus created by John Napier for calculation of products and quotients of numbers that was based on Arab mathematics. The abacus consists of a board with a rim; the user places Napier's rods in the rim to conduct multiplication or division. The board's left edge is divided into 9 squares, holding the numbers 1 to 9. The Napier's rods consist of strips of wood, metal or heavy cardboard. Napier's bones are three dimensional, square in cross section, with four different rods engraved on each one.

Pascal’s adding machine:

Pascal’s adding machine Blaise pascal, a French mathematician, invented a machine in 1642 made up of gears which was used for adding numbers quickly. This machine was named as adding machine or pascaline. Pascaline was capable of subtracting and adding. The Pascal's adding machine consisted of numbered toothed wheels having unique position values.

Leibnitz’s calculator:

Leibnitz’s calculator Leibnitz’s calculator was invented in 1671 by Leibnitz and was able to perform multiplication and division. The machine performed multiplication through repeated addition of number. Leibnitz’s machine used stepped cylinder each with nine teeth of varying lengths.

Jacquard’s loom:

Jacquard’s loom The Jacquard loom is a mechanical loom, invented by Joseph Marie Jacquard in 1801, that simplifies the process of manufacturing textiles with complex patterns. The loom is controlled by punched cards with punched holes , each row of which corresponds to one row of the design . Multiple rows of holes are punched on each card and the many cards that compose the design of the textile are strung together in order.

Babbage’s difference engine:

Babbage’s difference engine A difference engine is an automatic , mechanical calculator designed to tabulate polynomial functions. Both logarithmic and trigonometric functions can be approximated by polynomials, so a difference engine can compute many useful sets of numbers.

Babbage’s analytical engine:

Babbage’s analytical engine The Analytical Engine was a proposed mechanical general- purpose computer designed by English mathematician Charles Babbage. It was first described in 1837 as the successor to Babbage's difference engine, a design for a mechanical calculator. The Analytical Engine incorporated an arithmetical unit , control flow in the form of conditional Branching and loops, and Integrated memory , making it the first Turing-complete design for a general-purpose computer.

Hollerith's machine:

Hollerith's machine Herman Hollerith was an American statistician who developed a mechanical tabulator based on punched cards to rapidly tabulate statistics from millions of pieces of data. It uses punched cards for input, output and instructions

Mark 1 computer:

Mark 1 computer Mark I was an electro-mechanical computer constructed by prof. Howard A iken in U.S.A. in 1943. It can multiply two 10-digit number in 5 seconds.

The generation of modern computer :

The generation of modern computer

The first generation computer:

The first generation computer Some key concept of first generation computers:- Used vacuum tube Big and clumsy computers E lectricity consumption high Electric failure occurred regularly Large air conditioners were necessary Programming in machine language some computers of this generations are:- ENIAC EDVAC EDSAC UNIVAC-I

The second generation computers:

The second generation computers Some key features of second generation computers are:- Use of transistor Computers are smaller Generate less heat More reliable Faster than first generation computer Core memory developed Magnetic tapes and disks used Electricity consumption is lower For example: IBM 1401, CDC 3600 e tc.

The third generation computer:

The third generation computer Some key features of third generation computers are:- Integrated circuits developed Power consumption lower Computer smaller, faster and more reliable High-level language appeared For example:IBM-360 series, ICL-1900 series etc.

The forth generation computer:

The forth generation computer Integrated circuits, smaller and faster Micro computer series has developed Portable computers developed Great development in data communication Different types of secondary memory with high storage capacity

The fifth generation computer:

The fifth generation computer Some key features of fifth generation computers are:- Parallel-processing Many processors are grouped to function as one large group processors. Superconductors Faster transfer of information between the components of a computer. Applications of fifth generation computers: Intelligent system that could control the route of a missile. Word processors that could be controlled by means of speech recognition Programs that could translate documents from one language to another.

Digital computers:

Digital computers

PowerPoint Presentation:

The digital computers work upon discontinuous data. They converts the data into digits and all operations are carried out on these digits and add the digits. Digital computers are much faster than analog computers and far more accurate. Computer used for business and scientific applications are digital computers. Digital computers are classified into two ways: 1.purpose-wise 2.Size and performance wise

Purpose wise digital computers:

Purpose wise digital computers

1.Special-purpose computers- Special purpose computer is the one that is designed to perform a specific task. The instructions to carry out the task are permanently stored in the machine. 2.General-purpose computers- General-purpose computer is the one that can work on different types of programs input to it and thus be used in countless applications. :

1.Special-purpose computers- Special purpose computer is the one that is designed to perform a specific task. The instructions to carry out the task are permanently stored in the machine. 2.General-purpose computers- General-purpose computer is the one that can work on different types of programs input to it and thus be used in countless applications.

Size and performance-wise digital computers:

Size and performance-wise digital computers

Embedded computers:

An embedded system is a computer system designed to do one or a few dedicated and/or specific functions often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts. Embedded computers

Microcomputers :

Microcomputers A microcomputer is a computer with a microprocessor as its central processing unit. They are physically small compared to mainframe and minicomputers. Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense).


Minicomputers A minicomputer (colloquially, mini ) is a class of multi-user computers that lies in the middle range of the computing spectrum, in between the largest multi-user systems (mainframe computers) and the smallest single-user systems (microcomputers or personal computers). The class at one time formed a distinct group with its own hardware and operating systems.

Mainframe computers:

Mainframe computers Mainframes (often colloquially referred to as "big iron ") are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing. These computers Are designed to handle huge Volumes of data and information.

Super computer:

Super computer A supercomputer is a computer at the frontline of current processing capacity, particularly speed of calculation . Supercomputers are used for highly calculation-intensive tasks such as problems including quantum physics, weather forecasting, climate research, molecular modeling (computing the structures and properties of chemical compounds, biological macromolecules, polymers, and crystals), and physical simulations (such as simulation of airplanes in wind tunnels, simulation of the detonation of nuclear weapons, and research into nuclear fusion ).

Analog computers:

Analog computers

PowerPoint Presentation:

In analog computers , continuous quantities are used. Computations are carried out with physical quantities such as voltage, length, current, temperature etc. The devices that measures such quantities are analog devices e.g., voltmeter, ammeter. These computers operate by measuring rather than counting. The main advantage is that all calculations take place in parallel and hence are faster. For example:-

Hybrid computers:

Hybrid computers

PowerPoint Presentation:

Hybrid computers are computers that exhibit features of analog computers and digital computers. The digital component normally serves as the controller and provides logical operations, while the analog component normally serves as a solver of differential equations.

Thank you:

Thank you

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