Download c01- Introduction

Fundamentals of Computer: For undergraduate
courses in commerce and management
Author: ITL Education Solutions Limited
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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.
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Development of civilization
Fingers and pebbles for computing
computing needs also grew
Harnessing the power of computers
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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
Growth in commerce and
other human activities
Chronology
Fingers
Pebbles
Sand Tables
Abacus
Napier Bones
Slide Rule
Pascaline
Stepped Reckoner
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• Punch Card System
• Difference Engine
• Analytical Engine
• Hollerith's Tabulator
Other related dev.
• vacuum tube
• differential analyzer
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
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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
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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
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such as information retrieval computer-aided
design.
Can resolve complex mathematical equations
The Computer System
• Input Unit
• Central
Processing Unit
(CPU)
• Output Unit
•Memory/Storage
Unit
Intelligent thinking
machine?
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
Science
Education
Medicine and Health Care
Engineering/Architecture/Manufacturing
Entertainment
Communication
Business Application
Publishing
Banking
Assignments
IOA, IA, GA, Case !@#$