Fundamentals of Computer: For undergraduate courses in commerce and managementAuthor: ITL Education Solutions Limited

ISBN:9788131733349

Available through:Parama Publishers & Distributors Ltd.

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Introduction

Introduction A computer is • an electronic machine• devised for performing calculations and

controlling operations that can be expressed either in logical or numerical terms.

Development of civilization• Fingers and pebbles for computing• computing needs also grew• Harnessing the power of computers

Characteristics Of Computers• Speed

• Millions of instructions per second. 1 MHz (Megahertz) is one million instructions per second.

• Accuracy• Capable of doing only what it is instructed to

do• faulty instructions~ GIGO (Garbage In

Garbage Out)• Diligence

• No tiredness and/or lack of concentration• Reliability

• Some predetermined standard for operation without any failure

• Hardware level- built-in diagnostic capabilities

Characteristics Of Computers …Storage Capability

• Store large amounts of data • Recall almost instantaneously

The main memory~ relatively small • The secondary storage devices

• such as magnetic tape or disks. •brought into the main memory for processing

Versatility• Perform multiple tasks simultaneously• Play music and print a document and ...

Characteristics Of Computers …Resource Sharing

• Not isolated machines!• Computers today have the capability to

connect with each other• Apart from device sharing, data and

information can also be shared among groups of computers, thus creating a large information and knowledge base.

Development Of Computers

Chronology• Fingers• Pebbles• Sand Tables• Abacus• Napier Bones• Slide Rule• Pascaline• Stepped Reckoner

• Punch Card System• Difference Engine• Analytical Engine• Hollerith's

Tabulator

Other related dev.• vacuum tube• differential

analyzer

Growth in commerce and other human activities

Some Early Computers• MARK-I Computer 1937+

• IBM Sponsored• ABC Computer 1939

• Binary arithmetic, regenerative memory, logic

• Colossus 1944• 1800 vacuum tubes, programmable

• ENIAC 1946• 18000 vacuum tubes, 160 KW, 30 tons

• EDVAC, EDSAC, UNIVAC• Different technology

Generations Of Computers• First Generation (1940–56): Vacuum

Tubes• Memory- magnetic drums (data, programs)• Input- punched cards and paper tape • Output was displayed in the form of printouts• Large size, expensive to operate, unreliable,

lack of standard in programming• ENIAC, EDVAC, and UNIVAC.

• Second Generation (1956–63): Transistors• More portable. Still required air conditioning• Much smaller than vacuum tubes• Assembly language- used mnemonics• Computational time of these computers was

reduced to microseconds from milliseconds

Generations Of Computers …• Third Generation (1964–early 1970s): IC

• Integrated circuit (IC) technology• Faster- microseconds to nanoseconds• More portable and reliable• Cheaper- less power and generated less

heat, maintenance cost was quite low• Commercial production- easier and cheaper

• Fourth Generation (Early 1970+): Microprocessors• Size? AC Required? Portability? Reliability?• Cost?- production? maintenance?• Interconnection of computers- resource

sharing• Internet

Generations Of Computers …• Fifth Generation (Present And Beyond):

Artificial Intelligence• Mega Chips- Super Large Scale Integrated

(SLSI) •Millions of electronic components on a single chip•approximate the memory capacity of the human

mind

• Parallel Processing•multiple central processing units

• Artificial Intelligence (AI)• simulate and reproduce human behavior

• including thinking, speaking and reasoning•AI comprises a group of related technologies

• expert systems (ES), natural language processing (NLP), speech recognition, vision recognition, and robotics.

Classification Of Computers

Classification Of Computers- Purpose• General-purpose Computers

• Perform a range of tasks, Store numerous programs

• Generally lack speed and efficiency• Used in your schools and homes

• Specific-purpose Computers• Designed to handle a specific problem or to

perform a single specific task• Instructions (specific task) built into the

machine• Circuits are redesigned for another type of

task• Lacks versatility

• Fast and efficient• Airline reservations, satellite tracking, air

traffic control.

Data handling- Analog Computers• Works on the principle of measuring

• measurements obtained are translated into desired data

• Electrical parameters, such as voltages, resistances or currents, to represent the data

• Does not deal directly with the numbers.• measure continuous physical magnitudes (such as

temperature, pressure, and voltage), which are analogous to the numbers under consideration.

• Petrol pump may have an analog computer that converts the flow of pumped petrol into two measurements – the quantity of petrol and the price for that quantity.

• They give approximate results • Very fast in operation as all the calculations are

done in ‘parallel mode• The accuracy of analog computers is less

Data handling- Digital Computers• Data represented in a digital form

• process data (including text, sound, graphics, and video) into a digital value (in 0s and 1s)

• Analog quantities must be converted into digital quantity before processing

• Output is digital• The digital output has to be converted into

analog quantity if required. • Higher accuracy at a faster rate• The desktop PC at your home is a classic

example of digital computer.

Data handling- Hybrid Computers• Measuring feature of an analog

computer plus the counting feature of a digital computer

• Computational purposes- analog components

• Storage- digital memories• Uses analog-to-digital and digital-to-

analog converters

• Broadly used for scientific applications, various fields of engineering and in industrial control processes.

Functionality- Micro Computers

• Small, low cost digital computer• Consists of a microprocessor, a storage

unit, an input channel, and an output channel• all of which may be on one chip inserted into

one or several PC boards• Requires a power supply and connecting

cables, appropriate peripherals (keyboard, monitor, printer, disk drives, etc.), an operating system and other software programs can make a complete system

• Originally designed for individual users only• Now powerful to support businesses

functions • Networked together- serve multiple user

Functionality- Micro Computers …

• Desktop Computer• Most common micro computer• Intended for stand-alone use by an

individual.• Typically consist of a system unit, a display

monitor, a keyboard, internal hard disk storage, and other peripheral devices

• Laptop• Portable computer- travelling, built in

battery• Also known as notebooks• Smaller computers enclosing all the basic

features of a normal desktop computer• Expensive as compared to desktop

computers

Functionality- Micro Computers …

• Hand-held Computers• Also called Personal Digital Assistant (PDA)• Also known as palmtop computers• Stored in a pocket, used by the user is

holding it• Uses a pen or electronic stylus vs. keyboard • Can be connected to printer or a disk drive to

generate output or store data• Limited memory and are less powerful

Functionality- Mini Computers• Also called a mid-range computer • Higher performance than micro computers-

process and store less data than a mainframe • Often connected to a mainframe in order to perform

the auxiliary operations.

• Size~ of a two-drawer filing cabinet• Designed to meet the computing needs for

several people simultaneously in a small to medium size business environment. • Multi-user systems - capable of supporting from 4 to

about 200 simultaneous users• Centralized storehouse for a cluster of workstations or

as a network server.

• These are also used for real-time controls and engineering design work. High-performance workstations with graphics requirement.

Functionality- Mainframe Computers

• Mainframes are the second largest (in capability and size) of the computer family• high-volume, processor-intensive computing

• Centralization- It consists of a high-end computer processor, with related peripheral devices, capable of supporting large volumes of data processing, high performance on-line transaction processing systems, and extensive data storage and retrieval.

• However, a mainframe can usually execute many programs simultaneously at a high speed, whereas super computers are designed for single processes.

Functionality- Super Computers

• Special purpose machines, which are specially designed to maximize the numbers of FLOPS (Floating Point Operation Per Second)• More than one gigaflop/sec is considered a

super computer• Range of 400–10,000 MFLOPS• For solving scientific and engineering

problems• Contains a number of CPUs that operate in

parallel to make it faster. • Super computers help in many

applications such as information retrieval computer-aided design.

• Can resolve complex mathematical equations

The Computer System

Intelligent thinking

machine?

• Input Unit• Central

Processing Unit (CPU)

• Output Unit• Memory/

Storage Unit

The Computer System …Control unit and the registers

Types Of Input Devices• Keyboard• Pointing Devices

• Mouse, Trackball, Joystick,touch-screen, digitizer pen

• Camera• Scanners- different types• OCR software (Optical Character

Recognition)• OMR software (Optical Mark

Recognition)• MICR (Mag. Ink Character Reader)• Bar code reader- multiple types

Types Of Output Devices• Hard copy Vs. Soft copy• Printers-

• Dot matrix, daisy wheel, drum, ink-jet, laser• Plotters- pen based (Slow, high res.)

• flat, drum• Monitor

• Resolution, DPI, Refresh rate• LCD and CRT and …

Types Of Memory• Primary Memory

• RAM, ROM• Secondary memory

• Floppy/USB• Hard disk• Magnetic tape

Applications Of ComputerScienceEducationMedicine and Health CareEngineering/Architecture/ManufacturingEntertainmentCommunicationBusiness ApplicationPublishingBanking

AssignmentsIOA, IA, GA, Case !@#$