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Thursday, May 30, 2013

Advantages of computer


The advantages of the computers can be seen clearly in our daily lives. Every steps of our life is affected by computer in various ways. Nowadays without computer every tasks are look like impossible. The computer is playing very important role in every field of our life. Computers have changed the way people work. In daily life a large no. of activities are dependent in computers. Computers are used at home, in school, in offices, in shops, in hospitals, in hotels, in banks and many other areas. The main areas where computer is playing very important role are described below. Here are some advantages of computers:

Work in risky areas- Computer helps us in those risky areas where people cannot perform any activities. To make road in high mountainous areas we can send human less road making machine and control it by computer. To dig mines and tunnels we can use computers. To release the people who are trapped in mines. To dispose bomb. We can send the robots in high temperature area to release people who are trapped there.

Help Disable people- The person whose main organs of body are disable, can perform their daily task by the applications of computer. The people who cannot go outside and cannot see this world computers help them by the mean of internet. We can take the examples of great scientist Stefan hawking  who cannot speak, walk and cannot move any part of the body, now we can know what he want to say by the help of computer hardware and software. The person who do not have hands they can eat food by the help of robot. The persons who do not have legs can perform simple work by the help of remote control. They can close or open doors, off and on light, start motors and other task by the help of computer software’s.

Education
Nowadays almost all the schools and colleges use computers in classrooms and labs to teach students. A teacher can teach effectively by using computer –based presentations .Students can studies different subjects and complete their assignments by using different software’s in the computers.
The computer based training (CBT) or presentation is also called computer aid instructions (CAI) .In this method, computer is used as an aid to teach the students in the classroom. The web based training (WBT) is another type of CBT that uses Internet technology. Many websites provide online education. A lot of materials of different topics are available on these websites. They also provide online lecture and tutorials for the students. Edutainment is another type of CBT. It is a type of educational software that combines the education with entertainment. This software are use to teach student in a fun and in exciting way.

Government
With the help of computer, a government provides up to date information to citizen .The computers are used in all government departments and offices to perform various activities. Most of the government departments have their own websites. Filing system is upgraded in the government office now the offices use the electronic filing system. Most of the countries are using e-government system. Different government offices use computer to help the people who are in rural areas by the help of computer and internet. They provide the different information of future plan of development in their areas. They can conduct awareness program in the rural areas.

Medicine and Health Care
Nowadays computers are used in every area of the medical field. Such as laboratories, pharmacy, researches, scanning, monitoring, telemedicine, etc. In hospitals computers are used in the different medical unit such as ICU (intensive care unit) ECG (Electro Cardio Graph), operation theatre, recovery room, Medical ward, etc.
Most of the medical equipments used in hospitals are computerized. The equipments are used to monitor patient continuously. This equipment monitors the changes of heart rate Pulse rate, Blood pressure, Breathing and brain activity of the patient. If any unbalancing situation occurs, computer activates the alarming device, which creates sound and alerts the nurses or doctors.
Another use of computer in the medical field is the telemedicine. In telemedicine, you access medical care centre using computers video conferencing. Many surgeons also use computers aided surgery while they are in training. It is use to learn surgical techniques. Computers are helping the doctors to diagnose and many other purposes.

Science
Computer is used in all branches of science for various purposes. The scientist collects the latest information around the world through internet. All the scientific researchers are carried out using computers. Scientist can get accurate experimental results by using computer. By the help of the computer astronauts find out many facts of universe. They go to the different planets by rockets and find out their facts.

Entertainment
Computer is also paying very important role for the entertainment of people. Nowadays computer has become a mean of human entertainment. For examples, it can play games on computer by using different game software. Similarly, you can watch films and listen music on computers. You can listen music while you work on the computer .Nowadays the films and songs are mostly available on CD's and Pen Drive, DVDs or on the websites at very low cost. On the websites, you can view fine art, Images in online, museums and galleries. Many amusements and entertainment parks equipment's can control by computer. Nowadays films songs are edit by the computer and they make beautiful and full of action. Many science fiction films and cartoons are produce by animation in computer. Lighting system, stage lifting like theatric program can also perform.

Ecommerce
Ecommerce is also called electronic commerce of business. It is a financial business transaction conducted electronically between business partners over the internet with ecommerce transaction can occur very quickly and globally. The people can buy, sale and exchange the products or services using computer through internet today many mobile computers can also access the internet through wireless technologies. There are many applications of ecommerce such as home banking, buying stocks marketing and advertising products, providing services to the costumers. Nowadays many banks includes e-banking in their features.

Publishing
Computer is playing very important role in the field of publishing it is not possible to publish the newspapers, magazines, books etc. without using computer. The designer use word processors and graphics software to design the page of the books or magazines in the computer. We can print out big banners and flex print.

Travelling
Computer is also playing very important role in the field of travelling. It helps your travelling by car or airplane to arrive easily and safely at your destination. Today special electronic equipment are used in the car that controls various controls various activities of the car. These cars have “on-board navigation systems” that track the vehicle if it is stolen. Provide assistants, provide emergency services, provide direction etc. These cars also have GPS (Global positioning system) receiver that reports that your car location. Today many vehicles also include options such as screens with email and internet access, printers, fax capability etc.
Airlines also provide internet services to their passengers. The passengers can connect their laptop or notebook to the internet during their flights. Some airlines also provide laptop or other handheld computers to their passenger during their flights. Computer is also use d to monitor the air traffic.

Agriculture
Computer is also playing very important role in the field of agriculture the farmers use computer to get information about crops, market price of crops, to calculate cost etc. The students of agriculture use computer to get latest information about agriculture on the internet. The farmers can control the digging machine to dig field by the help of computer. We can serve domestic animal in time by setting the exact time to give water, food and also clean the cowshed by the help of computer.

Energy
Computer is also playing very important role in the field of energy, the energy companies use computers to locate or search natural oil (diesel and petrol), coal, natural gas and uranium similarly, electric power companies use computers to monitor the Power Station.

Industry
Computer is also playing very important role in industries to control the manufacturing system and continuous running of the machine. Computers are also use to monitor temperature, pressure, check the quality and accuracy of the products. In industry, Robots are used to perform most of the activities. A Robot is an automatic programmable machine that moves and performs mechanical tasks. A Robot acts like human being. Robot can working environment that is dangerous for human being such as opening chemical packages etc. It can perform repetitive tasks continuously without any break, at very high accuracy then humans.

War
Different countries use robots nowadays in war. They send robot in battle field with machine guns and order them through computers. We can use helicopters and airplanes by the help of computer we can navigate them from control station and through bombs in the targeted area. Many countries use computer to throw bomb in targeted areas.

Monday, May 27, 2013

History of Computer

The computer is one of the most advanced discoveries of making has got a long history, Around 3000 years before the birth of Jesus Christ, there were no any kind of number system . So people had to remember a lot of information. They felt the need to count the cattle. Then they started counting using their fingers. But the limited numbers of finger had made difficult for them to remember more facts. So they used stone for counting. As result around fifth century Hindu philosophers could develop new methods of counting using numbers 1 to 9. In 8th Century Alkhawarism of raq developed 0. Since there are ten digits there are ten digits these number systems methods was called decimal system.

Generations of Computer
A generation of computer refers to the state of improvement in the development of a computer system. In terms of technological development of computer systems. In terms of technological developments over times, computer has been broadly classified into five generation. A major technological development that fundamentally has changed the way computer operate, resulting in increasingly , smaller, cheaper, more powerful and more efficient and reliable devices characterize each generation of computer. In the history of computer there is four generation of computer. The generation of computer can be classified by the device used in memory and processor.

First generation (1946-1955) [vacuum tubes/thermionic valves]
The first generation computer operated on the principle of thermionic emission. They used thermionic valves also known as vacuum tubes and machine language was used for giving instructions. The first generation computers used stored program concept. First, the programming of first generation computer was done in machine language (instruction were written in binary digits 0s and 1s)
Features of first generation of computer
-The electronic circuitry was based on thermionic valves and vacuum tubes.
-Occupied very large space, slow, inefficient and unreliable due to low accuracy.
-The power consumption was very high and generated much heat.
-Electrostatic tubes (internal), paper tape, punched cards, magnetic tapes are were used.
-Programming mainly at the hardware level.
-Operating instructions were different in different computer depending upon the task for which the      computer was to be used.
-Used stored program concept.
-The computer of this generation were very large in size called mainframe computer or room sized computer.
Examples of first generation of computers:
Harvard Mark I (electromechanical), Whirlwind, ENIAC, EDSAC, UNIVAC I, UNIVAC II, UNIVAC 1101, RCA BIZMAC, NCR CRC 102A, NCR CRC 102D, Honeywell Datamatic 1000, Burroughs 220, IBM models 604, 650 (drum memory), 701, 702, 704, 705, 709.

Second Generation (1956-1965) [Transistor/electronic switching device]
The second generation of electronic computers began with the development of the transistor (transistor also called electronic switching device). A transistor transfer electric signal across a register. Transistor was highly reliable compared to tubes. Transistor was far more superior in performance on account of their miniature size, smaller power consumption and heat production.
Features of the second generation computer were:
-They were compact and hence occupied less space.
-Because of absence of heating the power required to operate them was very low.
-The operating speed was much higher.
-Transistor reduced the size-1/200th
-Magnetic core, magnetic drums- (main memory and storage device)
-Much faster, more reliable, better speed and could handle enormous amount of data.
-Machine independent “high level language” such as COBAL (Common Business Oriented Language) and -FORTRAN (Formula Translator) were introduced to simplify programming.
-Transistor is also termed as electronic switching device.
The examples of second generation computers;
UNIVAC 1107, UNIVAC III, RCA 501, Phil co Transact S-2000, NCR 300 series, Honeywell 800, 400 series, General Electric GE 635, GE 645, GE200, Control Data corp. CDC 1604, 3600, 160A, LARC, Burroughs B5000, 200 series.

Third Generation (1964-1975) [Integrated Circuit, LSI and MSI]
The third generation of computer began with the development of the integrated circuit. The input and system of third generation computer are keyboard and Monitor respectively. High level language is used in those computers. Improved disk storage was used for storage purpose.
Characteristics of third generation computers:
-Large Scale integrated circuits.
-10 million circuits per square foot.
Examples of third generation computers:
Burroughs 6700, Control Data 3300, Control Data 6600, Control Data 7600, Honeywell 200, IBM system/360, system 3, system 7, NCR century series, RCA spectra 70 series, UNIVAC 9000 series, General Electric GE 600 series, GE 235.

Fourth Generation (1975-current) [VLSI, Microprocessors]
The technology used in fourth generation computer very large scale integrated circuits (VLSICs) and microprocessors. The input units are keyboard, Mouse, Scanner. The output unit Monitor.
High level language and Non procedural language are the language use in those computers. The storage unit is hard disk.
Characteristics of fourth generation computers:
-Very large Scale Integration.
-Continued miniaturization.
-Billions of circuits per cubic foot.
Examples of fourth generation computers:
IBM system 3090, IBM RISC 6000, IBM RT, ILLIAC IV, Cray 2 XMP, HP 9000

Fifth generation computer (coming generation) [Artificial Intelligence, Neural Network, Expert system, ULSI]
These computers are incomplete. Researchers are going on the development of this computer. These computers will have been developed that will be able to converse with people and will able to mimic human sense, manual skills, and intelligence. For this purpose the concept of artificial intelligence is being used. Researchers are planning to produce biochips also called organic chip that are to be used in fifth generation computers.
Many projects have been created in the world for the fifth generation of computer.
-The ICOT program in Japan.
-DARPA project in USA Defense Advanced Research Project Agency.
-MCC project in USA Microelectronic and Computer Technology Corporation.
-Intelligent Knowledge Based System (IKBS) is the central elements of fifth generation’s computers.
-These will no superconductor technology with little or no resistance greatly improving the speed of information flow.
-The machine will incorporate Ultra Large Scale Integration (ULSI)
-Aim to able to solve highly complex problems, which require great intelligence and expertise when solved by people.
-They are intended to be able to cope with large subset of natural language and draw on very large -knowledge and draw on very large knowledge base.
-Neural network, export system, set of natural language are the central element of this generation.
-Biochips are also called termed as organic chips.
-          Parallel processing
-          High speed logic and memory chips
-          High performance, micro- miniaturization

Super Computer
-Most powerful, fastest, largest and expensive computer in the world.
-A single structure is primarily found on super computer.
-A number of RISC (Reduced instruction set computer) processor is used in super computer and its word length 64 bit.
-They are the state of the art machines designed to perform calculations as fast as the current technology allows.
-It is used to solve extremely complex and large scale problem, simulations of atomic explosions, aircraft design, movie animation, mathematical calculation or number crunching, satellite communication, fluid dynamics, geological data, rocket launching in space.
-Other name of super computer is number crunching.
-It was developed by Cray in the one year of 1976. It was the first in the history of the computer.
-Number of processor is 4-16.
-Multiple numbers of users.
-Most expensive (ten millions of dollars)
-The manufacturers of super computer are: IBM, SILICON, GRAPHICS, FUJSTU, INTEL, etc.
-These are fastest as they employ 1000’s of processors,
-100’s of GB of RAM, 1000’s GB of secondary storage.
-Used only by governmental agencies and large international corporations.
-Examples: CRAYI/II/III, CYBER-205, HITACHI-810/20, CRAY-XMP and NEC-500 are some popular super computers.

Mainframe computer
-Mainframes are computer that supports 100 or 1000 of user simultaneously.
-They are also called “Enterprise Server”.
-Multiple no. of users.
-Word Length = 32 bit to 64 bit.
-Number of processor is 1-4.
-Clock speed is greater than 100 MHZ.
-Process data at very high rate.
-They can run multiple operating systems. Hence they are called – VIRTUAL MACHINES.
-They handle a large amount of I/O device which are arranged in separate CABINETS or FREMES hence the name.
-Less expensive than super computer.
-Used for processing large amount of data, business and for specific purpose.
-User work with terminal [An input/output device at which data centers or leaves a computer system] e.g. may be bank mainframe.
-Generally consists of multiple processors, GB’s of memory and TB’s of storage.
-Cost in millions of dollars.
-It was developed by J.Presper Eckert and John Mauchly in the year of 1951. It was the first mainframe computer in the history of computer.
-Examples: ICL 2950/10, IBM 1401, IBM 4381, 1CL 39 series.
-The first UNIVAC I mainframe computer was delivers to the Census Bureau.
Applications
-They are used in large financial transactions.
-Enterprise Resource Planning (ERP)
-Industry and consumer statistics.
-Census.

Mini Computers:
-These were introduced by digital equipment Corporation (DEC) [first Minicomputer 12 bit, PDP-8] in 1960.
-Introduces by Kenneth H. Olsen in 1965.
-They can process more data and can support more I/O devices.
-They are less powerful than mainframe computers but more powerful than micro computer. Hence they are called MID-RANGE COMPUTERS.
-They cater to the needs of 4-200 users at a time.
-They are used in business as a centralized computer or as an internet server.
-They are less expensive than Mainframe computers. Examples include PDP 11, IBM 8000 series, etc.

Microcomputer
Depending on size, Microcomputers are of three types:
1.      Desktop computers:
They are used in single location, cheap, and have good storage. Example includes: Apple, IBM.
2       Laptop computers:  
      Portables computer are also called as the notebook computers or mobile computers. They are smaller in size, more expensive and are rechargeable. Examples include Apple, Acer, and Hewlett Packard (HP).
3         Hand-held computers:
Also called as Personal Digital Assistants (PDA’s), palmtop or mobile device. They are smaller in size, have smaller in size, have smaller display and input device is generally and electronic stylus. Their storage capacity is small. Example includes Apple Newton, Franklin eBook man. These are the history maker computers.
  
Mechanical Era/ the age of mechanical calculator
The significant early computing tools is ABACUS, was developed in 1000-1500 AD, a wooden rack holding parallel rods on which different sizes balls are stung. The arithmetic operation can be carried out with the help of beads on the wire. The frame consists of upper parts and lower parts. The upper part is called heaven and lower is called earth. Each part consists of five beads. This is used for addition and subtraction. In 1500, Leonardo Da Vinchi develops mechanical calculator, which was very heavy. A Scottish mathematician, John Napier (1614) invented another calculator which was made up of bone had more functionally add and multiplication of numbers. These are analog computer which have been replaced modern times by pocket calculators. The significant evolution of computing system was the invention by French mathematician, Blaise Pascal (1642). La Pascal machine could also multiply, divide and square root. In 1822 a professors of mathematician, Thomas (Charles Xavier Thomas) developed a machine called differential engine was the first commercially mechanical calculators. Charles Babbage (1792-1871) at Cambridge was developed the first digital computer. By 1822 he built an automatic mechanical calculator called difference engine. Unfortunately, Babbage analytical engine was never completed because its design required fabrication precision beyond that was feasible at that time. In 1840 Augusta (first programmer) suggested binary storage.
In 1887 an American statistician Herman Hollerith constructed a tabulating machine to compute the statics of 1890 US census. He used the punch card to store data. This machine can read 200 punched cards per minutes. In 1900 Johan Amberose Fleming invents the vacuum tube to store data and instruction, which was very big. The major step in the evolution of computer system is invention of punch cards which was first used during the US similarly; Lee de frost invented triode and semiconductors. After his retirement in 1913 Thomas J Watson becomes president of the company which becomes international business Machine Corporation in 1924.

Electronic Era/Age of Electronic Mechanical Computer
The electronic era was the time when the computers were made with electronics components. Following are some of the historical keys and dates in this invention era.
1937- John V. Attansoff Designed the first special purpose digital electronic computer. Professor Howard Akine constructed electro mechanical computer named mark I, which can perform according to pre programming instructions automatically. It was based on Charles Babbage principle after 100 years of his death. Although it was very huge with 51 feet long and 8 feet height and 3 feet wide using 1800 vacuum tubes, similarly Howard Aiken modified Mark 1 and invented Mark II which was 19000 vacuum tubes.
1945- John W Mauchly and Presper Eckert built ENIAC (Electronic numerical integrator and calculator) for the US Army . ENIAC was the first machine to use more than 2000 vacuum tubes and 18000 vacuum tube ENIAC  was the first high speed general purpose electronic digital computer was produce.
1946- UNIVAC (Universal automatic computer) was designed by Presper Eckert and John Mauchly, inventors of the ENICA. The UNIVAC was completed in 1950. It was the first commercial computer produced in the United States.
1948- Howard Aiken developed the Harvard Mark III, also known as ADEC (Aiken Dahlgrem Electronic Calculator) was an early computer that was partly electronic and partly electronic mechanical. It was built at Harvard University under US Navy.
1950- National Bureau of Standard (NBS) introduced its standards Eastern Automatic Computer with 10000 newly germanium diodes in its logic circuits, and the first magnetic disk drive designed by Jacob Rainow.
1952- Remington Rand bought the ERA in 1951 and combined the UNIVAC product in1952; the UNIVAC 1101 was used to calculate the presidential election.
1953-Tom Watson and IBM introduced model 604 computers, its first with transistors which becomes the basic of the model 608, the first solid state computers for the commercials market.
1964- IBM produce SABRE, the first airline reservation tracing system for American airlines, IBM announce system 360 all purpose computer using for 8 bit character word length.
1968- DEC introduced the first minicomputer, the PD-8 named after the mini skirt, DEC was founded in 1975 by Kenneth H. Olsen who came for the sage project at MIT and began sales of PDP in 1960.
1969-development began son Arpanet, founded by DOD (Department of Defense)
1970- First microprocessors and dynamic RAMs were developed. Hoff developed the first microprocessors 4004.
1971-Intel produces large scale integrated circuits that were used in the digital delay line, the digital device. Gilbert Hyatt at micro computer company introduced 4 bit 4004, a VLSI of 2300 components for Japanese company business to create a single chip for calculator. Similarly IBM introduces the first 8 inch memory disk; it was called then floppy disk.
1972-Intel made the 8 pins 8008 and 8080 microprocessors; Gary Kildall wrote his control program/ microprocessor disk operating system to provide instruction for floppy disk drivers to work with 8080 processors.
1973- IBM developed the first true sealed hard disk drive called Winchester after the rifle company, using two 30 MB plates. Robert Metcalfe at Xerox Company created Ethernet as the basic for Local Area Network.
1975- Bill Gates and Paul Allen found Microsoft Corporation.
1976- Job and woznik developed the Apple Personal Computer; Alan shugart introduced 5.5” floppy disk.
1980-IBM signed a contract with Microsoft Company of Bill Gates and Paul Allen and Steve Ballmer to supply an operating system for IBM PC model.
1984- Apple computer introduced the Macintosh personal computer in January 24.
1985- Microsoft developed Windows 85 was the first Window.
1991- World Wide Web (WWW) was developed by Tim Berner Lee and released by CERN.
1993- The first web browser called Mosaic was created by student Marc Andresen and programmer Eric Bina at NCSA in the first 3 month of 1993. The beta version of 0.5 of X UNIX was releases in Jan 23 1993.
1994- Netscape Navigator 1.0 was released DEC 1994, and given a way for soon gaining 75% world Market.
1996-Intel corporation Introduces pro(X 86) microprocessors
1997-Intel Corporation produced Pentium II
1999-Intel Corporation produced Pentium III

2000-Intel Corporation produced Pentium IV

Thursday, May 23, 2013

SEO



I welcome you all in my blog. Today I am going to share the information about the SEO. Today I will share what is SEO? What are the advantages of SEO? Why we do SEO.
Exactly what is SEO?
SEO is not a magic it is the idea or work which we have to do continuously to get website in high rank of search engines. SEO is the abbreviation of Search Engine Optimization. Suppose I have a website or blog, and I want the page visibility of my website is good or in top in all search engines like Google, Bing and many others. For this purpose I optimize my website or I do SEO of my website.
I give you an example of SEO.
If we search song in the Google. In the first page we get 10 results. The first website we saw in the page is the result of the SEO. The Site owner does SEO and he got his website in the first rank. So why we do SEO of our website.
Types of SEO.
On Line SEO- This is the type of SEO which we use directly in website. The SEO which is use while we are online.
Off Line SEO- This is the type of SEO which we do outside of Website. The SEO which we work in Offline.
At first the design of the website should be SEO friendly. The speed of the website should be high means the website should open fast. If the high graphics flash, animation is use in the website that will not open fast so the design of the website should be simple.
The layout of the Website should be SEO friendly. The navigation keys should be seen clearly in website and the position of sidebar should be in correct position.

Monday, February 8, 2010

Importance of computer education

computer education Computer is not only a storage devices.Through computer we can get connected to the world through internet.Computer education increase the chances of getting job.The knowledge of software and hardware education help to get the high salary job.Computer education helps to manage our own business.In banking system through internet we can know the transaction payment,stored amount in bank etc.The online shopping is increasing nowadays.Te knowledge of word processing, excel help to make the document.Through computer also we can give the knowledge and information to other computer also by the knowledge of computer networking education.
In job, in house, in industry, in school, in every sector there is use of the computer.Without knowing about or with out learning the computer education we can not use the computer properly.To develop the status of the computer education many universities, institution, school are opening .To work in different sector different type of the computer education is needed.
  • In bank there is use tally education as well as making journal, ledger etc.
  • In engineering the engineer should know about the computer education in his field for map making for civil engineer as well as for architecture.Many many top building can only design by the computer it is not only possible by pen and paper to make the big earthquake proof building there is need of computer and computer education for those person.
  • In medical sector there is high importance of the computer education.In treatment of the patient, making medicine etc.
  • In industrial to make different things ,to sure the amount of raw materials computer education is needed we can know the things which is going to be produced .
Education is the development of the human mind .It clears the darkness of our life.It is the third eye of the human beings .As well as the computer education is also important for all in the comparison of the other education.Computer education is use in every field and sector nowadays.
There are many ways where we can use computer education.Nowadays computer education becomes the urgent need of the present people.
The application of the computer is increasing day by day we can rule the society through computer education .Like the other education computer education is also the main part of our life.

Sunday, January 17, 2010

Network Topologies in computer

Network TopologiesBold Each computer or device in a network is called node.The arrangement or connection pattern of computers or nodes and other devices of the network is known as network topology.Speed and performance of the computer network depends upon the topology used.Basic topologies of network are: 1.Bus topology 2.ring topology 3.star topology.
1.Bus topology
In bus topology ,computers and other devices are arranged in a linear format .It uses a common backbone is also called Bus.it works as a communication medium and each workstation is connected with the coaxial cable and "T"connector.Data are transmitted on the network through the backbone using the computer destination address .If the address matches with the workstation address ,It receives the data.If the address does not match, the data passes to the next workstations and so on.
2.Ring topology
In ring topology computers are connected in the shape of the circle without any endpoint .Each workstation contains two neighbors for communication or an input and an output connection. The input connection of the workstation receives data and is transmitted to the next workstation through the output connection.So, in this topology ,the signal travel s in circle passing through each computer o the network because their are no terminates ends to the cable .It supports coaxial ,twisted pair and fiber optic cables.
Ring topology uses a token passing method to pass data from one computers to another .All the computers get equal opportunity to access the token .A workstation that need to transmit data captures the token .Data and destination address are added with the token and sent to the ring .If the destination computer receives the data properly , then it will send a positive acknowledgment .Otherwise ,it sends a negative acknowledgment to the source computer.
3.Star topology
In star topology ,all computer or network devices are connected through a central devices in the shape of a star structure .The common devices used for the central connection are hub and switch .The computer are connected to the hub or switch using unshielded twisted pair,shielded twisted pair or fiber optics cables.This is the most popular network topology used to connect computers and other devices in anetwork .In this topology ,the central point device (hub or switch) may regenerate the signal ,which helps to transfer data to a longer distance.

Thursday, January 14, 2010

Multimedia application of computer

computer multimedia equipments

INTRODUCTION OF MULTIMEDIA APPLICATION OF COMPUTER

computers have changed from huge mainframes to small desktop computers as time passed .The first personal computer could not produced sound .They just displayed the text on the screen .But over the years a number of new technologies have emerged which have extended the power of machine, faster chips, sound cards ,bigger monitors and so on .So, multimedia technology has emerged gradually.

Multimedia is a new technology .As the name implies ,multimedia is the integration of multiple forms of media .The word multimedia is made up of two separate words,"multi" and"media",which means many and materials , through which information may be transmitted .This includes text ,graphics ,animation ,video, sound and computer programs. These mediums are digitally controlled by computers .Multimedia enhances the information for better communication and understanding Multimedia upgrade kits(MUK)are available in the market for the upgrading of your pc .A MUK consists of the CD-ROM drive, sound card, speaker and microphone etc.

Types of media

Multimedia is the integration of multiple forms of media .The types of media in multimedia include:

Types and Description

Text: Displays’ alphanumeric character on the screen to present the information. It is the base of the layer of almost all programs.

Graphics: computer graphics make computer capable of displaying and manipulating pictures. It is a more powerful way to to illustrate information than the text.

Animation: Animation on computers is one of the chief ingredients of multimedia presentation .Animation is a simulation of movement created by displaying a series of pictures or frames .Cartoons on television are an example of animation.

Video: Video deals with recording and display of sequences of images at a reasonable speed to create an impression of movement .It describes images of real events stored in a digital form.

Sound: Sound is a significant aspect of exciting and successful multimedia application. Sound effects are used to accompany animation and increase the interactivity with the user.

Multimedia technology

Multimedia is a kind of powerful and popular technology in the computer in the field which manipulates text, photos, animation, video, etc.CD-ROM is used to store the data and information
in the multimedia technology it is also called the multimedia CD.The capabilities of multimedia technology to handle different types of media makes them suitable for wide range of application and users.
Multimedia computer system
Computer need different type of components to manipulate the data and information related to the multi media application Some of the components ar as follows:
computer
Software (Window Media player, Adobe illustrator ,Macromedia Flash etc.)
-CD-ROM
-CD ROM Drive
-Sound card
-Microphone
-Head phone
-Digital camera
-projector
Multimedia Application
The capabilities of multimedia technology to handle different types of media make them suitable for wide range of application and user. Some of the areas where multimedia could have direct impact are listed below :
- Video Games
-Multimedia in presentation
-Apply special effects in film
-Multimedia for public accessing
-Animated advertisement
-Foreign language learning
-Virtual reality.

Wednesday, January 13, 2010

computer network

computer networkCOMPUTER NETWORK
A computer network means two or more than two computers connected with each other to share data , hardware,software,and other resources .Other resources includes printers,hard disk ,CD drive etc.Telephone lines ,cables,satellite links ,radio waves and other communication techniques, interconnect computer in the network.

ADVANTAGE OF THE COMPUTER NETWORK
  • Computers in a network can access network-connected hardware devices like printers disk drives etc.

  • Information can exchange rapidly in computer network.

  • Computers in a network system share different software packages .

  • Data in a network environment can be updated from any computers .Updated data can be accessed by all computers of the network.
DISADVANTAGES OF COMPUTERS NETWORK
  • Failure of server stops application being available.

  • Network failure cause loss of data.

  • User work dependents upon network.

  • System opens to hackers.

NETWORK CATEGORIES On the basis of the size of the network, the distance it covers and the type of the line used in communication , the computers network is divided into three categories .They are;

  1. Local Area Network

  2. Metropolitan Area Network

  3. Wide Area Network

1.LOCAL AREA NETWORK

A local area network (LAN) is a network of computers that are relatively near with each other and are connected in a way that enables them to communicate by cables and a small wireless device.A LAN can consist of just two or three computers to exchange data or share resources or it can be include hundreds of computers of different kinds.Any network that exists with in a building ,or within a short distance is considered as LAN.

Features of local area network
  • The diameter is not more than a few kilometers.
  • A LAN offers bandwidth of 10 to 100 Mbps.

  • It is controlled by a single organization.
2.METROPOLITAN AREA NETWORK

A Metropolitan area network (MAN) is a network of computers with spreed over metropolitan area such as with in city.It connects two or more LAN together.A single organization or a group to share data and resources may operate MAN .ISP providing network communication within a city and the network communication with in a city and the network of different branches of a bank with in a same city are the examples of the MAN.

Features of Metropolitan Area Network

  • it covers a limited geographical area .
  • it may be owned by single or multiple organization.
  • it uses cable or wireless connections.
  • it uses private or public connection medium.

3.WIDE AREA NETWORK

A wide area network (WAN) is a network system of connecting two or more computers generally across a wide geographical area such as cities ,district and countries.This type of network uses i telephone lines ,satelite links and other long-range communication technologies to connect computers .

Features of Wide Area Network

  • it covers a large geographical area.
  • it is owned by multiple organizations.
  • it uses public connection mediums such as telephone lines,wireless technology etc.

Monday, January 11, 2010

Hardware of computer

computer hardware partsThe advantage using ram to store whatever you are working on at that moment is that RAM is very fast.
HARD DISK
The things is in your computer is totally stored in the computer.With out this anything cant be save or stored.
MOUSE
Mouse is used to click where we need .It has two bottom its like the shape of the mouse.The buttom are primary(left) buttom and secondary(right) buttom and in between them there is wheel.
KEYBOARD
Key board is gennerally used to type the text.It has words, numeric and differnet function.
With out hardware the computer is not complete or not redy for the work.

software of computer

windows vista cdComputer software is generally used to store digital data as a program and other kind of information read and written by computers.software some times used as a application software.
The characteristics of the software are ;
software can be developed
software are constantly outdated
most software are continues to be custom built
there are different types of software which are categorized following;
  1. system software
  2. programming software
  3. application software
software quality is very important speccially for commercial purpose like the system software microsoft office, microsoft window, etc. Microsoft is the popular software in the world.

C language in computer

javaC is a structred programming language.the most important feature of a structure programming language is that it uses blocks. A block is a collection of statement which is used to solve a particular programming .like in QBASIC , a structred programming language also support loop structure ,selection structure etc.Dennis Ritchie at Bell telephone Laboratories originally developed C in 1972 .After 1980 numerous compilers and interpreters had been written all sizes of computer , so the popularity of C language had become wide spread .C is also comes under high language but it is also called a middle level computer language because it combines elements of a high level language with some features of assembler . A high level language tries to give programmer everything through built in language .A low level language forces programmar to define function directly from the user level.As amiddle language C language manipulates bits , bytes and address . It is mostly used to write system program such as operating systems , languages, compilers, text editor ,language interpreters , utilities etc. C language is mostly used to design application software.It support structure programming with function procedure.