Fundamentals of Computer: For undergraduate courses in commerce and management Author: ITL Education Solutions Limited ISBN:9788131733349 Available through:

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

ISBN:9788131733349

Available through:Parama Publishers & Distributors Ltd.

Momtaz Plaza (3rd Floor) House 7 Road 4 Dhanmondi Dhaka 1205 Bangladesh

T +88 02 9611971-5 9661141 9662282

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 Computer

ScienceEducationMedicine and Health CareEngineering/Architecture/ManufacturingEntertainmentCommunicationBusiness ApplicationPublishingBanking

AssignmentsIOA, IA, GA, Case !@#$