Chapter #1

Q: - Briefly Describe Computer History

The history of computers starts out about 5000 years ago, with the birth of the abacus. It is a wooden rack holding horizontal wires with beads strung on them. When these beads are moved around, according to programming rules memorized by the user, all regular arithmetic problems can be done.

Q:-Briefly Describe Napier’s bones Works in History

John Napier, a Scottish mathematician, created logarithm tables to facilitate calculations. He also created a device using rods, also called Napier's bones to perform arithmetic calculations. These rods were widely used by accountants and bookkeepers.

Q: - What are the contribution of john von Neumann in History

Von Neumann contributed a new awareness of how practical and fast computers should be built. These ideas, usually referred to as the stored - program technique, became essential for future generations of high speed digital computers and were universally adopted. According to

Von Neumann theory "Data and program can be stored in the same memory. Thus the machine can itself alter either its program or internal data”

Q: - What are the advancement comes in 1950’s to 1960’s

In early 1950's, two important engineering inventions changed the image of the computer field. These discoveries were the magnetic core memories and the Transistor

Circuit Elements. This quickly found its way into new models of

 Digital computer

Card Readers,

Printers

Cathode-Ray-Tube

Accounting

Payroll

Inventory control

Ordering Supplies

Billing

Q: - What is pascal’s pascaline calculator?

Pascal invented a machine that had a system of gears. A one-tooth gear engages its single tooth with a ten-tooth gear once every time it revolves. It must make ten revolutions to rotate the ten-tooth gear once. Numbers could be entered and cumulative sums obtained by cranking a handle. Pasrnl's calculator was not a commercial success because these devices could not be built with sufficient precision for practical use.

Q: - Briefly Describe Charles Babbage Works in History

a series of very interesting development in computers was started in Cambridge, England by Charles Babbage, a mathematics professor. He began to design an automatic mechanical calculating machine, which he called a difference engine. BY 1822, he had a working model to demonstrate. It was intended to be steam powered and fully automatic, including the printing of the results. Babbage continued to work on it for the next IO years, but in 1833 he lost interest because he thought he had a better idea i.e. the construction of what would now be called a general purpose, fully program-controlled. Automatic mechanical digital computer. Babbage called this idea an Analytical Engine.

Q: - What are the use of punched cards of Hollerith?

In 1890, Herman Hollerith developed the first electro-mechanical punched card tabulator. The tabulator could read information that had been punched into cards. These cards were maintained in stack form. Solutions to different problems could be stored on different stacks of cards and accessed when needed.

Q: - What are the more recent advancement in Computer History

In 1980’s very large scale integration (VLSI) in which hundreds of thousands of transistors were placed on a single chip become more and more common.In the manufacturing of computer processor chips, the Intel and Motorola coarporation were very compitative into 1980,However, the Japanese government Corporations were announced very a big competitive plan to into design the and 1980s.

Q: - List the computer Generations

1.       First Generation -Vacuum Tubes

a.       ENIAC (Electronic Numerical Integrator and Calculator)

b.      UNIV AC (Universal Automatic Computer)

2.       Second Generation – Transistors

3.       Third Generation -Integrated Circuits \ IC (Integrated Circuit)

4.       Fourth Generation – Microprocessors

5.       Fifth Generation - Present and Beyond: Artificial Intelligence

a.       Analog Computers

b.      Digital Computers

c.       Hybrid Computers

Q: - What is First Generation -Vacuum Tubes Computers

Computers of this generation used vacuum tubes to perform calculations.

 Vacuum tubes were expensive because of the amount of material and skill needed to manufacture

Them. Computers Vacuum of this tubes get generation hot and were burn very out.

Conditioning were needed to house them because of the heat generated by the vacuum

Tubes.

The most important computers were ENIAC and UNIV AC - I.

Q: - What is ENIAC (Electronic Numerical Integrator and Calculator)

It was the first general-purpose electronic digital computer designed by John  William Machly .it consumed and 140 kilowatts and doing 5000 addition per second. ENIAC was a decimal rather than a binary machine. That is numbers were represented in decimal form and arithmetic was performed in the decimal system. The major drawback of ENIAC was that it had to be programmed manually by setting switches and plugging and unplugging cables

Q: - UNIV AC (Universal Automatic Computer)

In 1947, Eckert and Machly formed Eckert-Machly Computer Corporation to manufacture computers commercially. Their first successful machine was UNIV AC, which was delivered to US bureau of census in 1951. It was actually the first computer developed for commercial use. It was intended for both scientific and commercial applications.

Q: - Second Generation - Transistors

TRANSISTORS

Transistor, was invented by Bardeen,

William Shockley and  Willilhn Brattain  in 1947.

Advantages

200 transistors are about the same size as one vacuum tube in a computer.

Much less expensive than a vacuum A than a transistor vacuum tube can work 40 times faster

Do not get hot and burn out like a vacuum tu9

e way smaller, cheaper, as a vacuum and tube dissipates to less construct heat than ,computers. a vacuum tube but can be used in the

As had high compared to processing first speed. Generation Most of computers, these second computers generation used magnetic computers core were memory smeller’s internal arithmetic and storage. Logic The unit, use of ·second-generation low level and computers high level enjoyed the programming use of languages more such complex as. 

COBOL, BASIC, mples Pasc:al of and second-generation Assembly etc. computers and are provision IBM of 7094 system series, IBM software 1400 with series,the

CDC computers164etc. Ex

Third Generation -Integrated Circuits

The concept o.f the IC was developed by Jack St. Clair Kilby in 1958.

An First IC IC is was about imvented 1/4 and square used in􀂦h in and 1961 can . contain thousands of transistors

The major invention of third generation of computers was the development of IC (integrated circuit). A single IC chip contains thousands of transistors. The computer became smaller in size, faster, more reliable, and lower in price. And also became very common in medium to large-scale business. These computers used magnetic core memory as internal storage. The most successful computers of this generation were IBM sys  em/360 and DEC PDP-8, the others were UNIV AC 1108, UNIV AC 9000 and IBM 370 etc.

Fourth Generation – Microprocessors

the The first microprocessor microprocessor is a in 1971 complete for Intel, processing which circuitry was named on a as chip. "Intel Ted 4004 Hoff ". produced

2.            Modern microprocessors are usually less than one square inch and can contain million of electronic circuits.

3.            Used in many electronic devices today such as wristwatches, microwave ovens and cars. )

1.2.5 Fifth Generation - Present and Beyond: Artificial Intelligence

( Fifth generation computing devices, based on artificial intelligence,  are still in

make being development used artificial todaystagein e Though ligence use a there of reality. are parallel some Quantum processing applications,such and computation as and voice superconductors molecular is recognition,thatand helping nano­areto

Analog Computers

Anal􀀂g computers use electronic or mechanical phenomena to model Jhe problem being solved by using one kind of physical quantity to represent another.

Digital Computers

( Digital computers process data in numerical form using digital circuits. The digital computers perform arithmetic and logic operations with discrete values.􀀗

Hybrid Computers

( Hybrid Computers are the combination of analog and digital computers . Hybrid computers use analog-to-digital conversion and digital-to-analog conversion, and may input or output either analog or digital dat'9

Classification of Computer

•             Super Computer

•             Mainframe Computer

•             Mini Computers

•             Micro computer

Supercomputers

Supercomputers are the most powerful computers made, and physically they are some of the largest. These systems are built to process huge amount of data, and the fastest supercomputers can perform more than 1 trillion calculations per second. Some supercomputers - such as Cray T90 system - can house thousands of processors

Supercomputers can cost tens of millions of dollars and consume enough electricity to po er dozens of homes. Because of their size and cost, supercomputers are relatively rare, used only by large corporations, universities, and government agencies that can afford them.

Mainframe Computers

The largest type of computer in comm n use is the mainframe. Mainframe computers are used in large organizations like insurance companies and banks where many people need frequent access to the same data, which is usually organized into one or more huge database. Airlines use large mainframe systems for flight scheduling, reservations, ticketing, and meeting a range of customer service needs.

In traditional mainframe enviroru:ent, each user works at a computer terminal. A terminal is a monitor and a keyboard connected to a mainframe.

Minicomputer

inicomputers got their name because of their small size. These computers have less processmg power than mainframe computers but have high processing power than microcomputers. Like mainframe, minicomputersc􀀤n support number of user's input and

server output machines. requirements. These Normallycomputers.are .- \piiniless comput􀀰sexpensi \ . y<lhan are used mainframe in networked computes and environment are idealas 

for mainframe organizations computers. that The could HP not 3000 afford is an mainframe example of or do not minicomputetJ need Jhe processing power of

Microcomputer

Microcomputers (also referred to as personal computers) are typically developed for IBM indiviclual called users. its first These are less microcomputer powerful the machines IBM-PC.as

Microcomputers are available in different models i.e. desktop models, laptop compub, and pocket computers etc.

POCKET (PALMTOP) COMPUTER

Pocket computers have been designed to allow people to keep lots of information close to hand wherever they happen to be. A pocket computer has to have small, light batteries that last a long.\

LAPTOP COMPUTER

The main aim of a laptop is that the persons using it can have all programs and data from their desktop computer on a portable computer. The person using a laptop should be able to run all the same software on the laptop as runs on larger, desktop computers as laptop computers have the same types of operating system as desktop ones.

Impact of Computers and Internet on Society

EDUCATION

Educational institutes, from primary to university level, are using computers for vario learning ac ·vities. A large number of learning programs (tutorials) are available on almost every subjec ;

BUSr:CompESS

Computer is now being widely used in business and industry. Comp􀀋ter e informationmade

systems are used to keep tra of huge transactions. They also allow transactions to be made from any whare world.

ONLINE BANKING

The advent of the Internet and the popularity of personal computers presented an opportunity for the banking industry. For years, banking institutions have used powerful computers to perform millions of transactions. Nowadays, ATMs are installed everywhere; these are all computerized and connected together. These can be used to draw money from any branch of that bank at any time of the day. Customers are now also connected to

APPLICATION IN RETAILING APPLICATIONS

Modem stores are quickly incorporating computer system for a number of reasons.

Firstly these systems allow the billing of items to be done at great speed. They accept credit cards, allowing customer to purchase goods without cash.

COMPUTER SIMULATIONS

Computer Simulation is the use of computer to represent the dynamic responses c one system by the change in behaviors of another system modeled after it. Computt simulations are widely used in educational institutes to make clear the understanding of th working of various systems e.g. simulation of aeroplane is a part of training of the pilot.

APPLICATION IN ENTERTAINMENT

The advancement of computer science has also helped entertainment industry. Nowadays computer can be used to watch television shows being broadcasted on Internet. watch movies, listen to music and play games.

OTHER AREAS

Today computers are being used in many other areas to save time and cost. These include publishing where documents can be written and saved on a computer. This is accomplished by a word-processing application such as Microsoft Word. These applications allow the writers to correct and print the document in very short time. These documents can also be sent from one place to anther via Internet.

Programming Languages

The set of instructions (executed by the CPU) to

sofre particular problem is called computer program (or simply program).

LOW LEVEL LANGUAGES s􀀁

Low level languages provide J the programmer with a high degree of control, but they require a detailed knowledge of the hardware to be used. They are really only required for advanced programming needs. There are two main types of low level languages.

•             Machine language

•             Assembly language

MACHINE LANGUAGE

Th! processor within a computer can perform various operations, each of whi􀂈h is identified by an operation code (or opcode). It is possible to write a program directly in machine code by using the correct opcodes in the correct sequence into memory, alongwith the required data values and parameter values.

ASSEMBLY LANGUAGE

Assembly language is very close to machine language. The commands are represented in Assembly Language by short names called mnemonks (pronounced as Ne-Monies). For example Id means Load Accum􀀳lator with a particular data value.

IDGH LEVEL LANGUAGES

High level languages are close to human languages and far from the machine language.

•             FORTRAN (FORmula TRANslation)

In 1957. FORTRAN appeared as the first major high ]eve] languages appeared in the form of FORTRAN. FORTRAN stands for Formula Translation. The language was designed at IBM for scientific computing. It was mainly used for scientific purposes-.

BASIC (Beginners All-purpose Symbolic Instruction Code)

BASIC was designed to allow students to write programs using time-sharing computer terminals. BASIC was intended for easy learning programming concepts. The design principles of BASIC were: •           Be easy for beginners to use.

•             Be a general-purpose language.

•             Allow advanced features to be added for experts (while keeping the language simple for beginners).

•             Be interactive.

•             Provide clear and friendly error messages.

•             Respond fast for small programs.

•             Not require an understanding of computer hardware.

COBOL (Common 􀀁usiness Oriented Language)

Though FORTRAN Was good at handling numbers, it was not so good at handling input alict1 output, which mattered most to business computing. COBOL was designed as the language for businessmen.

LISP

LISP stands for List Processing language. It was designed for Artificial Intelligence (AI) research. Because it was designed for such a highly specialized field, its syntax (programming rules) was very different from ordinary languages.

PASCAL (PASCAL is a language named after a Scientist Pascal)

Pascal was designed in a very orderly approach; it combined many of the best features of the languages in use at the time, COBOL, FORTRAN, and ALGOL.

•             C and C++

·               C was developed in 1972 by Dennis Ritchie while working at Bell Labs. C is very commonly used to program operating systems such as UNIX, Windows, and Macintosh OS etc. It is also very useful for compiler writing.

Visual Basic

It was the first visual development tool from Microsoft, and it was designed to compete with C, C++, Pascal and any other well known programming languages. When it came out, Visual Basic wasn't very successful.

JAVA

Sun Microsystems began developing a language with the primarily purpose to control microprocessors used in consumer items such as cable receivers, VCR's, toasters, and also for personal data assistants (PDA). Java offers powerful capabilities of network programming, Internet applications and GUI

(Graphical User Interfacef.\

Lan􀀉Jge Translators

Language translators are the programs that translate a high or level language program into machine code.

•             Assembler

•             Compiler

•             Interpreter

Assembler

An assembler is a program that translates an assembly language program into machine code.

1.7.2 Compiler

A compiler is a program that translates a source program (written in some high-level programming language) into machine language (or machine code). A compiler first reads the whole program before executing it.

1.7.3 Interpreter

An interpreter on the other hand, looks at each line of the program, decides what that line means, checks it for possible errors and then executes that line. If one of the lines is executed repeatedly, it must be scanned and analyzed each time, greatly slowing dowri the solution of the problem at hand.