1.1.1 Definition, characteristics and applications of computer
- The word “Computer” is derived from the Latin word “Computare” which means to calculate.
- Definition of Computer: An electronic device which accepts raw data from users and processes it to give meaningful results and store the important data for future use is called Computer.
- Data: The raw facts about anything are called data. Examples: Students data are name, address, class, roll no. etc.
- Instruction: Instruction is specifying what must be done to the data.
For examples: SP = 1000 and CP = 700 are data. To find profit (SP>CP) = SP-CP =1000-700= 300 - Information: The processed data which gives meaningful results is called information. Example: 300 is profit.
- Hardware: Computer hardware is the collection of physical components that make up a computer. In other words we can say that hardware covers all parts of a computer that are tangible objects. Examples of hardware are input devices like keyboard and mouse, output devices like printer and monitor, storage devices like disk drive and the computer itself.
- Software: Software refers to the component of the computer which do not have a material form, such as programs, data, protocols etc. Software refers to something intangible. Basically, software is a program written by a programmer which controls/operates specific parts of the computer or specific application.
Software is often divided into two categories:
System software: It includes operating system and all utilities that enable the computer to function.
Application software: It includes programs that do real work for users. For example, word processors, spreadsheets, and database management systems fall under the category of application software. - Firmware: A set of micro instructions stored in a chip is called firmware. Micro instructions are hardware level instructions which are directly executed by the hardware. Firmware is loaded into the equipment, either at the time it is manufactured or later, by the person installing the equipment or the person using it. In other words, Firmware, which is added at the time of manufacturing, is used to run user programs on the device, Firmware is a combination of software and hardware. ROMS, PROMS and EPROMS that have data or programs recorded on them are firmware. The best example of firmware is BIOS (Basic input output system).
- Program: A sequence of instructions that perform certain tasks is called Program.
- User: The person who uses the computer is called user.
- Peripheral: The input, output and storage devices which can be connected to the system cabinet are called Computer Peripherals or peripheral devices. Examples: Printer, Scanner, Card reader etc.
Assignment-1
1. Define the term computer. Compare hardware, software and firmware.
1. Define the term computer. Compare hardware, software and firmware.
Characteristics of a computer: (5 marks)
Computer is the most useful and powerful machine which can perform various tasks. The major characteristics of computers are speed, storage, accuracy, versatility, diligence, automation, word length, non-intelligent etc.
- Electronic
- Speed
- Storage
- Accuracy
- Versatility
- Diligence
- Automatic
- Non-intelligent
- Word Length
- Electronic: A computer is an electronic machine developed to perform calculations and control operations that can be expressed either in logical or numerical terms. Most computers' parts are electronic devices which are made of semiconductor chips.
- Speed: A computer can work at very high speed and is much faster than humans. One second is a very long time for a computer to perform a task. The time used by the computer to perform an operation is called the processing speed. The speed of the computer is calculated in MHz (Megahertz) , that is one million instructions per second. Today, a powerful computer can perform billions of operations in just one second.
- Storage: A computer can store a large amount of data permanently. Users can use this data at any time. We can store any form of data in a computer: text, graphics, pictures, audio and video, etc. The storage capacity of the computer is increasing rapidly. We can store data, information, etc in storage devices such as hard disk, pen drive in terms of KB, MB, GB, TB, PB, etc.
- Accuracy: Accuracy concerns the act of providing results without any error. Computers can process large amounts of data and generate error-free or, say, almost 100% error free results. A modern computer performs millions of operations in one second without any error. However, sometimes, we get wrong output due to the fault in the data, instruction or program which is known as Garbage in Garbage out (GIGO).
- Versatility: A computer can perform various types of tasks. Interestingly, the same computer can be used for various purposes Such as accounting, generating pay slip, playing games, listening to music, watching movies, typing and printing documents, sending emails, and much more.
- Diligence: Unlike human beings, a computer never feels tired or bored to do a task repeatedly for a long time. No wonder, the computer can perform the same task with the same speed and accuracy even for hours and days so long as it is provided with a suitable environment and correct program.
- Automation: Computers can be programmed to perform a series of complex tasks automatically. For that reason, the computers have been used for quality control in the industries which perform the task without getting any instructions from the operator.
- Non-intelligent: Although the computers are incredibly faster, more powerful and accurate than humans, it does not have a common sense- it can't think and decide itself to do any task.
- Word Length: Word length refers to the number of bits that the CPU can process in parallel at a time. Modern processors, including embedded systems, usually have a word length of 8, 16, 24, 32 or 64 bits, while modern general purpose computers usually use 32 or 64 bits. The power of a computer depends upon the word length. Higher the world length, better the performance of computers.
Computers have been an integral part of our daily life in this modern age. Nothing is absolute: everything has its flaws and weaknesses. And, the same applies in computers too, However, its merits weigh much heavier than demerits.
Advantages of Computer
- A computer is much more reliable, fast, versatile and useful in doing repeated jobs and is less prone to data loss.
- Computers can search free-text as well as structured data to find a specific data value.
- Computers are the best tools when it comes to predicting to a large extent what type of results a business plan would throw up.
- Computer saves time and also gives error free result.
- Computers provide highly accurate answers and calculations.
- Using a computer, one can analyze the data and make informed decisions about the future course of action.
Disadvantages of Computer
- It costs much to have computer equipment and software.
- Highly-skilled IT (Information Technology) personnel is required.
- Computers decrease/discourage physical activities affecting health in a major way.
- Software configurations do not necessarily communicate with each other.
- Need repair, update and maintenance frequently.
- Misunderstandings can arise quickly and be difficult and time-consuming to solve.
Assignment-2
1. List out the characteristics of computer.
2. List out the merits and demerits of computer.
Application of Computer
1. List out the characteristics of computer.
2. List out the merits and demerits of computer.
Although, the early computers were mainly used for mathematical calculations to predict impacts of bombs, path of artillery shells, calculate some other numerical values etc. With the development of technology, modern computers have played an important role in society. In modern days, computer are used in different fields, some of them are as follows:
- Education: Computers have been used in education to help the students in their study and the teachers to organize and prepare their teaching materials and collect required information from the internet. Due to the availability of eBooks in CD, DVD and on the internet, computers have been a very helpful and essential device for students and teachers for their better education.
- Offices: Modern computers are very necessary and useful resources in the office. In offices, computers are used in preparing the reports, letters, notice, salary sheet, income and expenditure reports etc. So that efficiency and work speed of the employees will be improved. Generally Microsoft Office and accounting packages are used in an office to handle the daily works.
- Health and Medical field: Computers have played a vital role in the medical field as it has been used in hospitals to help doctors, nurses and technicians to diagnose disease, getting information about patients, disease and drugs. Similarly, many computerized equipment such as CT scan machines, eye testing machines and many computerized machines are used for experiment and disease diagnosis. Surgeons also use the computerized device to get the information about the condition of the patient.
- Home: Nowadays computers are used in home to store personal records, photos, videos, playing games, listening music, watching movies etc. It can be used even to connect the internet and use services like email, chatting, online TV streaming, downloading songs and movies etc.
- Bank: Computerized technology has brought revolution in the bank. Unlike in the manual system, deposit and withdrawal became quickly in computerized banks. A computer is also used to maintain ledger, to provide the online service to the customers who need services from their home, to transfer amounts etc. For these purposes, there is a central computer called server. In banks, mostly in head offices, this stores all the necessary information centrally so that it can be accessed from any branch office of the bank. Because of this, a customer can get services from any branch of the bank.
Due to the computer with network facility, nowadays banks also provide ATM service to customers so that a customer with an ATM card can perform a cash transaction immediately with the ATM machine at any time and from any place. - Industries: Computers have been used in industries for various purposes such as keeping the employees record, income and expenditure record, salary sheet, measurement and display of physical quantity, quality control of production etc. The different tasks which are risky for human beings are being done by computerized robots in industries so that human life will not be at risk.
- Science and technology: Since the invention of early computers, it has been a great aid for the mathematician and scientist for doing fast and correct calculation. Scientific and technological research work involves complex and massive calculations.
In many cases, simulation is also required. Such massive calculation and simulation are not possible in paper or by hand calculations. Modern computers are best for scientific research for the analysis of data. - Recording and film studio: The modern computer can also be used for recording songs, movies and dialog. It is also used in film studies to do animation and movie production. It is used to make the movie more interesting, more popular and more attractive.
Nowadays, the music and songs can be recorded at different tracks, time and place. Similarly, movie editing also has been very easy due to the computerized system. - Weather forecasting: Weather forecasting is not an easy task as it is done after the analysis of the images, temperature, wind speed, humidity etc. of different places, which is sent by the satellite. The analysis of these large data is not possible without the use of computers. Computers analyze the direction of the wind, cloud structure, past data and many other factors to forecast the weather. Due to the use of specific computers, we can see that BBC, CNN and other news channels predict the weather forecasting.
- Reservation: By using the computer with internet facilities, the reservation for the air ticket, train ticket, bus ticket etc. becomes possible. It also stores information regarding passengers such as name, address, age, destination, data etc. Due to the credit card and debit card facility the passengers can reserve and purchase the tickets even from their own home computer.
- Military: Since the past, computers have been used by the armed forces for testing and development of military devices like missiles, tanks and bullets etc. The pilotless fighter planes can carry missiles and drop at the pin-point area by the use of the computerized system. It also plays an important role in military communication.
- Communication: Due to the invention of the internet, modern computers are massively used for fast, reliable and cheap communication all around the world. Text, photo, animation, email, voice etc can be exchanged between two computers through the internet.
- Library: We can use computers in the library also to keep the records of books, magazines, reports, newspapers and other documents. We can keep also records of the library members with which books they have borrowed with detailed information.
Nowadays, many books are available in the digital format in the form of CDs and DVDs too. Similarly, many e-books are kept on the internet as e-library to read such e-books also, we need computers. - Desktop publishing house: Desktop publishing house is the place where the design and publication of different materials like books, magazines, journals etc take place. Before publishing these materials, they should be designed properly. Nowadays, there are many computerized software for desktop designing and publishing which makes it very easy and efficient. Some of the desktop publishing software such as MS-Word, Adobe PageMaker and others, which is used to manipulate computer systems.
Assignment-3
1. List out the application areas of computer.
1. List out the application areas of computer.
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History of Computer
The development of personal computers has taken a long period of time to extend the use of computers at present. There were not the advanced technologies in the ancient days. So it passed through several phases to become this phase in the present days.
The development of computers from ancient days to present days can be classified into the THREE Era which are as follows.
| A) Mechanical Calculation Era | B) Electro-mechanical Era | C) Electronic Computers Era |
|---|---|---|
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A) Mechanical Calculation Era:
1. Abacus- Abacus is the first calculating device.
- An abacus consists of a rectangular frame containing a number of rods or beads which is divided into two unequal parts called heaven and earth.
- The lower part is called, an earth consists of 5 beads and the upper part called, a heaven consists of 2 beads.
- By moving the beads, it is used for counting as well as to find addition and subtraction.
- A skilled abacus operator can work on addition and subtraction problems at the speed of a person equipped with a hand calculator.
- John Napier, a great Scottish mathematician invented ”Principle of logarithm” i.e. log in 1614 AD.
- Then, based on his own principle, he invented a simple device containing 10 rods made of ivory sticks marked with numbers in 1617 AD, called Napier’s Bone.
- People could use it for faster multiplication and division.
- Based on the principle of John Napier, William Oughtred, an English mathematician, made a simple device called slide rule in 1624 AD.
- It had multiple rulers marked with numbers in one pack.
- People could use it for faster multiplication and division also.
- It was still in use in the 1960’s by the NASA engineers of the Mercury, Gemini and Apollo programs which landed men on the moon.
- Pascaline was invented by Blaise Pascal in 1642 AD, when he was just 19 years old.
- He invented that device to help his father who was a tax collector.
- It had some cogs and gears rotating in complement to each other and it could do addition and subtraction up to 8 digits only.
- Multiplication and division were done by repeated addition and subtraction respectively.
- Later a computer programming language was called ‘Pascal’ to honor him for his contribution in the development of computers.
- Gottfried Wilhelm Von Leibniz was a great mathematician who managed to build a four function (addition, subtraction, multiplication and division) calculator in 1671 AD on the basis of Pascaline.
- It could find square roots too.
- Although the Stepped Reckoner employed the decimal number system, Leibniz was the first to advocate use of the binary number system which is fundamental to the operation of modern computers.
- Joseph Marie Jacquard invented Jacquard’s Loom in 1801 AD.
- This Loom was the first to use a Punch Card.
- Later the same Punch Card technology was used for Computer Programming.
- The Difference Engine was developed by Charles Babbage in 1822 AD, which was equal to the size of a room.
- The Difference Engine was his first invention and it was powered by a steam.
- The Difference Engine was fully automatic for mathematical calculation.
- He obtained government funding for the development of Difference Engine due to the importance of numeric tables in ocean navigation.
- By promoting their commercial and military navies, the British Government had managed to become the earth’s greatest empire.
- Charles Babbage also designed another engine in 1833 AD, but unfortunately he was unable to complete it.
- The analytical Engine contained all components as follows:
- The store equivalent to memory.
- The mill equivalent to CPU.
- The input section using punched cards.
- The output section using punched cards.
- And modern computers are based on it. That’s why, for all his contribution, he is known as “father of Computer”.
- Lady Augusta Ada was the admirer and follower of Charles Babbage.
- She was fascinated by the idea of Babbage.
- She suggested Babbage use a binary number system for the computer program and data to be fed into the Analytical Engine on Punch Card.
- She gave the concept of computer programming for the first time, so she is considered as “First Computer Programmer”.
- She invented subroutine and the importance of looping.
- She found that the same set of Punch Cards could be reused to repeat certain instructions.
- One programming language “ADA” was named to honor her for her great contribution in computer programming.
- The very first census of 1790 had only required 9 months, by 1880 the U.S. population had grown so much that the count for the 1880 census took 7.5 years. Automation was clearly needed for the next census.
- The census bureau offered a prize for an inventor to help with the 1890 census and this prize was won by Dr. Herman Hollerith for the development of the Tabulating Machine.
- By using the similar ideas of Jacquard’s Loom he made a Tabulating Machine in 1886.
- It could process on the Punch Cards and perform the census calculation faster and accurately.
- Hollerith’s technique was successful and the 1890 census was completed in only 3 years at a savings of 5 million dollars.
- He established his own company called Tabulating Machine Company (TMC).
- Later, TMC joined with another company and established IBM in 1923 AD.
- IBM is the largest computer manufacturing company in the world even today.
Assignment-4
1. List out the name of inventions along with respective inventors in mechanical era.
1. List out the name of inventions along with respective inventors in mechanical era.
B) Electro-Mechanical Era
10. Mark-I- It was designed by Howard Aiken.
- This was the first programmable digital computer.
- This machine works on decimal not in binary format.
- Its dimension was 51 feet long, 8 feet tall and 3 feet wide.
- It had a 50 feet rotating shaft running its length, turned by a 5 horsepower electric motor.
- It consumed a lot of electricity and emitted a lot of heat.
- It was also called IBMASCC (International Business Machine Automatic Sequence Control Calculator).
- This project was a joint partnership between IBM and Harvard University.
- It can automatically perform a sequence of arithmetic operations: addition, subtraction, multiplications, division and table reference.
- It could add or subtract two of numbers in three – tenth of a second, multiply them in four seconds.
- J. V. Atanasoff was a Professor of Physics and mathematics, with the help of his graduate student Clifford Berry; he built a machine that could solve different types of mathematical problems successfully tested in 1942.
- This machine was the first to store a charge on a capacitor, which is how today computers store information in their main memory (RAM).
- It used 45 vacuum tubes for internal logic and capacitors for storage.
Assignment-5
1. List out the name of inventions along with respective inventors on electro-mechanical era.
1. List out the name of inventions along with respective inventors on electro-mechanical era.
C) Electronic Computer Era:
12. ENIAC (Electronic Numerical Integrator and Calculator) [1943-1946]- Dr. John W. Mauchly and John Presper Eckert developed ENIAC at the Moore School of Electrical Engineering of the University of Pennsylvania in 1946, USA.
- It was the first electronic computer.
- This had no moving parts except the input and output.
- ENIAC was developed for military needs and was used for many years to solve ballistics (fire weapons) achieved problems.
- The addition of two numbers was achieved in 200 microseconds and multiplication in 2000 microseconds.
- It occupied a room measuring 9m*15 m and contained 18,000 vacuum tubes, more than 70,000 resistors, 10,000 capacitors, 60,000 switches and weighed 30 tons.
- It was invented by John W. Mauchly and J. Presper Eckert.
- He was the first to introduce the stored program concept in a computer.
- It used a binary number system rather than decimal numbers for its operation.
- It had almost 6,000 vacuum tubes and 12,000 diodes and consumed 56 KW of power.
- It covered 490 square foot of floor space and weighed nearly 7 tons.
- The machine requires 30 personnel to operate.
- This machine ran till 1961 at a research laboratory.
- It was invented by Maurice Wilkes at Cambridge University, England in 1949 AD.
- It also used vacuum tubes.
- Although started after EDVAC, it was completed before EDVAC.
- It uses a binary number system.
- Both input and output used paper tape.
- This machine was used to calculate a table of squares and a list of prime numbers.
- It was invented by John W. Mauchly and J. Presper Eckert.
- This computer was the first commercial computer and general purpose computer produced in large quantities.
- Before this, all the computers were either used for defense or census.
- The UNIVAC was also the first computer to come equipped with a magnetic tape unit and was the first computer to use buffer memory.
Assignment-6
1. List out the name of inventions along with respective inventors in electronic era.
1. List out the name of inventions along with respective inventors in electronic era.
Generation of Computer:
Generation of Computer terminology is a change in technology a computer is/was being used. Initially generation of computers was used to distinguish between varying hardware technology.
There are 5 generation of computers which are as follows:
First Generation Computer (1940-1956)
- The computers which were made approximately between 1940 and 1956 AD are classified as the first generation computer.
- These computers had used vacuum tubes as their memory and processing devices.
- Vacuum tube was developed by Lee De Forest in 1908 AD.
- Technology: Vacuum tube was used as its main components.
- Processing Speed: Processing speed was measured in Milli-second.
- Input/output Device: Punch Card was used as input / Output devices.
- Computer Type: Computers were electro-mechanical.
- Memory: Vacuum tube was used as a memory device.
- Storage Device: First Punch cards used and later magnetic drums were used as storage devices.
- Operation Mode: Computers should be set up manually as there was no operating system invented.
- Reliability and Accuracy: The computers were not fully reliable and accurate.
- Programming Language: Machine Level Language was used for computer programming.
- Size and Cost: The size of the computer was very large and its cost was also very expensive.
- Availability: The Computers were only available to the military purpose and university research.
- Power Consumption and Heat Emission: Computers consumed a lot of electricity power and emitted a lot of heat.
- Portability: Computers were not portable because of its huge size.
- Examples: ENIAC, EDVAC, UNIVAC etc.
Vacuum Tube: A vacuum tube is a hollow glass cylinder containing a positive electrode and a negative electrode between which is conducted in a full or partial vacuum tube. A grid between these electrodes controls the flow of electricity.
The major disadvantages of tubes include the fact that they require bulky power supplies and the high voltages can present an electric shock hazard.
2) Second Generation Computer (1956-1963)
- The computers which were made approximately between 1956 and 1963 AD are classified as the Second generation computer.
- These computers had used transistors and diodes as their memory devices.
- Transistor was invented by three scientists John Bardeen, William Shockley and Walter Brattain in 1947 AD and won the Nobel Prize in 1956 AD for it.
- Technology: Transistor was used as its main components.
- Processing Speed: Faster processing speed as it was measured in Micro-second.
- Input/output Device: Punch Card was used as input / Output devices.
- Computer Type: Computers were electro-mechanical.
- Memory: Magnetic Core (Ferrite) was used as internal memory.
- Storage Device: Magnetic Tape was used as a secondary storage device.
- Operation Mode: Computers should be set up manually as there was no operating system invented.
- Reliability and Accuracy: These were more reliable and accurate than first generation computers.
- Programming Language: Assembly and High Level Language such as FORTRAN (Formula Translation), COBOL (Common Business Oriented Language) etc. were used for computer programming.
- Size and Cost: The Computers were smaller in size and less expensive than 1st generation computers.
- Availability: The Computers were available for general purpose.