computer components and development

7/21/2019 Computer Components and Development

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Joanne BillonesBS Accountancy 2-1D

A computer is an electronic device, operating under the control of instructions stored in

its own memory, that can accept data, process the data according to specied rules,

produce results, and store the results for future use

!omputers process data into information Data is a collection of unprocessed items,

which can include te"t, num#ers, images, audio, and video Information conveys

meaning and is useful to people

COMPONENTS OF THE COMPUTER SYSTEM

$he computer system consists of four parts%&1' (ardware, &2' Software, &)' Data, and

&*' +sers

Hardware consists of the

mechanical parts that

mae up the computer as

a machine $he hardware

consists of physicaldevices of the computer

$he devices are reuired

for input, output, storage

and processing of the data

.ey#oard, monitor, hard

dis drive, /oppy dis

drive, printer, processor

and mother#oard are some

of the hardware devices

Software is a set of instructions that tells the computer a#out the tass to #e

performed and how these tass are to #e performed Program is a set of instructions,written in a language understood #y the computer, to perform a specic tas A set of

programs and documents are collectively called software $he hardware of the computer

system cannot perform any tas on its own $he hardware needs to #e instructed a#out

the tas to #e performed Software instructs the computer a#out the tas to #e

performed $he hardware carries out these tass Di0erent software can #e loaded on

the same hardware to perform di0erent inds of tass

Data are isolated values or raw facts, which #y themselves have no much signicance

or e"ample, the data lie 29, January , and 1994 ust represent values $he data is

provided as input to the computer, which is processed to generate some meaningful

information or e"ample, 23, January and 133* are processed #y the computer to give

the date of #irth of a person

Users are people who write computer programs or interact with the computer $hey are

also nown as skinware, liveware, humanware or peopleware 4rogrammers, data entry

operators, system analyst and computer hardware engineers fall into this category

Components of Computer Hardware




An input deice is any hardware component that allows you to enter data and

instructions into a computer ive widely used input devices are the ey#oard, mouse,

microphone, scanner, and 5e#cam

An output deice is any hardware component that conveys information to one or more

people $hree commonly used output devices are a printer, a monitor, and speaers

$he s!stem unit is a case that contains electronic components of the computer that

are used to process data $he circuitry of the system unit usually is part of or is

connected to a circuit #oard called the motherboard $wo main components on the

mother#oard are the processor and memory $he processor , also called the !4+ &central

processing unit', is the electronic component that interprets and carries out the #asic

instructions that operate the computer Memory consists of electronic components that

store instructions waiting to #e e"ecuted and data needed #y those instructions 6ost

memory eeps data and instructions temporarily, which means its contents are erased

when the computer is shut o0

Stora"e deices hold data, instructions, and information for future use or e"ample,

computers can store hundreds to millions of customer names and addresses Storageholds these items permanently A computer eeps data, instructions, and information on

storage media 7"amples of storage media are +SB /ash drives, hard diss, optical

discs, and memory cards A storage device records &writes' and8or retrieves &reads'

items to and from storage media Storage devices often function as a source of input

#ecause they transfer items from storage to memory

A communications deice is a hardware component that ena#les a computer to send

&transmit' and receive data, instructions, and information to and from one or more

computers or mo#ile devices A widely used communications device is a modem

!ommunications occur over ca#les, telephone lines, cellular radio networs, satellites,

and other transmission media




DE#E$OPMENT OF COMPUTIN% DE#ICES

+ntil the development of the rst generation computers #ased on vacuum tu#es, there

had #een several developments in the computing technology related to the mechanical

computing devices $he ey developments that too place till the rst computer was

developed are as follows%

• Calculating Machines ABA!+S was the rst mechanical calculating device for

counting of large num#ers $he word ABA!+S means calculating #oard 9t

consists of #ars in hori:ontal positions on which sets of #eads are inserted $he

hori:ontal #ars have 1; #eads each, representing units, tens, hundreds, etc

• Napier’s Bones was a mechanical device #uilt for the purpose of multiplication

in 1<1= &D #y an 7nglish mathematician John >apier

• Slide Rule was developed #y an 7nglish mathematician 7dmund ?unter in the

1<th century +sing the slide rule, one could perform operations lie addition,

su#traction, multiplication and division 9t was used e"tensively till late 13=;s

• Pascal’s Adding and Subtraction Machine was developed #y Blaise 4ascal 9t

could add and su#tract $he machine consisted of wheels, gears and cylinders

• eibni!’s Multiplication and Di"iding Machine was a mechanical device that

could #oth multiply and divide $he ?erman philosopher and mathematician

?ottfried @ei#ni: #uilt it around 1<=)

• Punch Card S#ste$ was developed #y Jacuard to control the power loom in

1;1 (e invented the punched card reader that could recogni:e the presence of

hole in the punched card as #inary one and the a#sence of the hole as #inary

:ero $he ;s and 1s are the #asis of the modern digital computer




• Babbage’s Anal#tical %ngine An 7nglish man !harles Ba##age #uilt a

mechanical machine to do comple" mathematical calculations, in the year 12)

$he machine was called as di0erence engine @ater, !harles Ba##age and @ady

Ada @ovelace developed a general-purpose calculating machine, the analytical

engine !harles Ba##age is also called the father of computer

•

Hollerith’s Punched Card &abulating Machine was invented #y (erman(ollerith $he machine could read the information from a punched card and

process it electronically

$he developments discussed a#ove and several others not discussed here, resulted in

the development of the rst computer in the 13*;s

%enerations of Computer

$he computer has evolved from a large-si:ed simple calculating machine to a smaller

#ut much more powerful machine $he evolution of computer to the current state is

dened in terms of the generations of computer 7ach generation of computer is

designed #ased on a new technological development, resulting in #etter, cheaper and

smaller computers that are more powerful, faster and ecient than their predecessors!urrently, there are ve generations of computer 9n the following su#sections, we will

discuss the generations of computer in terms of%

1 the technology used #y them &hardware and software',2 computing characteristics &speed, ie, num#er of instructions e"ecuted per

second',) physical appearance, and* their applications

First %eneration '()*+ to (),-./ Usin" #acuum Tu0es

Hardware &echnolog# $he rst generation of computers used vacuum tu#es

for circuitry and magnetic drums for memory $he input to the computer wasthrough punched cards and paper tapes $he output was displayed as printouts

Software &echnolog# $he instructions were written in machine language

6achine language uses ;s and 1s for coding of the instructions $he rst

generation computers could solve one pro#lem at a time Co$puting Characteristics $he computation time was in milliseconds

Ph#sical Appearance $hese computers were enormous in si:e and reuired a

large room for installation Application $hey were used for scientic applications as they were the fastest

computing device of their time %'a$ples +>9Cersal Automatic !omputer &+>9CA!', 7lectronic >umerical

9ntegrator And !alculator &7>9A!', and 7lectronic Discrete Caria#le Automatic

!omputer &7DCA!'

$he rst generation computers used a large num#er of vacuum tu#es and thus

generated a lot of heat $hey consumed a great deal of electricity and were e"pensive

to operate $he machines were prone to freuent malfunctioning and reuired constant

maintenance Since rst generation computers used machine language, they were

dicult to program

Second %eneration '(),- to ()-1./ Usin" Transistors




Hardware &echnolog# $ransistors replaced the vacuum tu#es of the rst

generation of computers $ransistors allowed computers to #ecome smaller,

faster, cheaper, energy ecient and relia#le $he second generation computers

used magnetic core technology for primary memory $hey used magnetic tapes

and magnetic diss for secondary storage $he input was still through punched

cards and the output using printouts $hey used the concept of a stored program,

where instructions were stored in the memory of computer Software &echnolog# $he instructions were written using the assembly

language Assem#ly language uses mnemonics lie ADD for addition and S+B for

su#traction for coding of the instructions 9t is easier to write instructions in

assem#ly language, as compared to writing instructions in machine language

(igh-level programming languages, such as early versions of !B@ and

E$EA> were also developed during this period Co$puting Characteristics $he computation time was in microseconds

Ph#sical Appearance $ransistors are smaller in si:e compared to vacuum

tu#es, thus, the si:e of the computer was also reduced Application $he cost of commercial production of these computers was very

high, though less than the rst generation computers $he transistors had to #eassem#led manually in second generation computers

%'a$ples 4D4-, 9B6 1*;1 and !D! 1<;*

Second generation computers generated a lot of heat #ut much less than the rst

generation computers $hey reuired less maintenance than the rst generation

computers

T2ird %eneration '()-* to ()3(./ Usin" Inte"rated Circuits

Hardware &echnolog# $he third generation computers used the Integrated

ircuit !I" chips 9n an 9! chip, multiple transistors are placed on a silicon chip

Silicon is a type of semiconductor $he use of 9! chip increased the speed and the

eciency of computer, manifold $he ey#oard and monitor were used to interactwith the third generation computer, instead of the punched card and printouts

Software &echnolog# $he ey#oard and the monitor were interfaced through

the operating system perating system allowed di0erent applications to run at

the same time #igh$level languages were used e"tensively for programming,

instead of machine language and assem#ly language Co$puting Characteristics $he computation time was in nanoseconds

Ph#sical Appearance $he si:e of these computers was uite small compared to

the second generation computers Application !omputers #ecame accessi#le to mass audience !omputers were

produced commercially, and were smaller and cheaper than their predecessors %'a$ples 9B6 )=;, 4D4 11

$he third generation computers used less power and generated less heat than the

second generation computers $he cost of the computer reduced signicantly, as

individual components of the computer were not reuired to #e assem#led manually

$he maintenance cost of the computers was also less compared to their predecessors

Fourt2 %eneration '()3( to present./ Usin" Microprocessors




Hardware &echnolog# $hey use the %arge &cale Integration !%&I" and the 'ery

%arge &cale Integration !'%&I" technology $housands of transistors are integrated

on a small silicon chip using @S9 technology C@S9 allows hundreds of thousands of

components to #e integrated in a small chip $his era is mared #y the

development of microprocessor Microprocessor is a chip containing millions of

transistors and components, and, designed using @S9 and C@S9 technology $his

generation of computers gave rise to 4ersonal !omputer &4!' Semiconductor

memory replaced the earlier magnetic core memory, resulting in fast random

access to memory Secondary storage device lie magnetic diss #ecame smaller

in physical si:e and larger in capacity $he linking o( computers is another ey

development of this era $he computers were lined to form networs that led to

the emergence of the 9nternet $his generation also saw the development of

pointing devices lie mouse, and handheld devices Software &echnolog# Several new operating systems lie the 6S-DS and 6S-

5indows developed during this time $his generation of computers

supported )raphical *ser Inter(ace &)*I' ?+9 is a user-friendly interface that

allows user to interact with the computer via menus and icons (igh-level

programming languages are used for the writing of programs Co$puting Characteristics $he computation time is in picoseconds

Ph#sical Appearance $hey are smaller than the computers of the previous

generation Some can even t into the palm of the hand Application $hey #ecame widely availa#le for commercial purposes 4ersonal

computers #ecame availa#le to the home user %'a$ples $he 9ntel *;;* chip was the rst microprocessor $he components of

the computer lie !entral 4rocessing +nit &!4+' and memory were located on a

single chip 9n 131, 9B6 introduced the rst computer for home use 9n 13*,

Apple introduced the 6acintosh

$he microprocessor has resulted in the fourth generation computers #eing smaller and

cheaper than their predecessors $he fourth generation computers are also porta#le andmore relia#le $hey generate much lesser heat and reuire less maintenance compared

to their predecessors ?+9 and pointing devices facilitate easy use and learning on the

computer >etworing has resulted in resource sharing and communication among

di0erent computers

Fift2 %eneration 'Present and Ne4t./ Usin" &rti5cia6 Inte66i"ence

$he goal of fth generation computing is to develop computers that are capa#le of

learning and self-organi:ation $he fth generation computers use &uper %arge &cale

Integrated !&%&I" chips that are a#le to store millions of components on a single chip

$hese computers have large memory reuirements

$his generation of computers uses parallel processing that allows several instructions to#e e"ecuted in parallel, instead of serial e"ecution 4arallel processing results in faster

processing speed $he 9ntel dual-core microprocessor uses parallel processing

$he fth generation computers are #ased on +rticial Intelligence !+I" $hey try to

simulate the human way of thining and reasoning Articial 9ntelligence includes areas

lie 7"pert System &7S', >atural @anguage 4rocessing &>@4', speech recognition, voice

recognition, ro#otics, etc




C$&SSIFIC&TION OF COMPUTERS

$he digital computers that are availa#le nowadays vary in their si:es and types

!omputers are #roadly classied into four categories #ased on their si:e and type%&1'

6icrocomputers, &2' 6inicomputers, &)' 6ainframe computers, and &*' Supercomputer

Microcomputers

6icrocomputers are small, low-cost

and single-user digital computer $hey

consist of !4+, input unit, output unit,

storage unit and the software

Although microcomputers are stand-

alone machines, they can #e

connected together to create a

networ of computers that can serve

more than one user 6icrocomputers

include destop computers, note#oocomputers or laptop, ta#let computer,

handheld computer, smart phones

and net#oo

-esktop omputer or Personal

omputer !P" is the most common

type of microcomputer 9t is a stand-alone machine that can #e placed on the des

7"ternally, it consists of three units%ey#oard, monitor, and a system unit containing

the !4+, memory, hard dis drive, etc 9t is not very e"pensive and is suited to the

needs of a single user at home, small #usiness units, and organi:ations

.otebook omputers or %aptop resem#le a note#oo $hey are porta#le and have all thefeatures of a destop computer $he advantage of the laptop is that it is small in si:e

&can #e put inside a #riefcase', can #e carried anywhere, has a #attery #acup and has

all the functionality of the destop @aptops can #e placed on the lap while woring

&hence the name' @aptops are costlier than the destop machines

.etbooks are smaller note#oos optimi:ed for low weight and low cost, and are

designed for accessing we#-#ased applications Starting with the earliest net#oo in late

2;;=, they have gained signicant popularity now >et#oos deliver the performance

needed to enoy popular activities lie streaming videos or music, emailing, 5e# surng

or instant messaging $he word net#oo was created as a #lend of 9nternet and

note#oo

/ablet omputer has features of the note#oo computer #ut it can accept input from a

stylus or a pen instead of the ey#oard or mouse 9t is a porta#le computer $a#let

computer are the new ind of 4!s

#andheld omputer or Personal -igital +ssistant !P-+" is a small computer that can #e

held on the top of the palm 9t is small in si:e 9nstead of the ey#oard, 4DA uses a pen

or a stylus for input 4DAs do not have a dis drive $hey have a limited memory and




are less powerful 4DAs can #e connected to the 9nternet via a wireless connection ver

the last few years, 4DAs have merged into mo#ile phones to create smart phones

&mart Phones are cellular phones that function #oth as a phone and as a small 4! $hey

may use a stylus or a pen, or may have a small ey#oard $hey can #e connected to the

9nternet wirelessly $hey are used to access the electronic-mail, download music, play

games, etc

Minicomputers

6inicomputers are digital computers, generally used in

multi-user systems $hey have high processing speed and

high storage capacity than the microcomputers

6inicomputers can support *F2;; users simultaneously

$he users can access the minicomputer through their 4!s

or terminal $hey are used for real-time applications in

industries, research centers, etc

Mainframe Computers

6ainframe computers are multi-user, multi-programming and high

performance computers $hey operate at a very high speed, have

very large storage capacity and can handle the worload of many

users 6ainframe computers are large and powerful systems

generally used in centrali:ed data#ases $he user accesses the

mainframe computer via a terminal that may #e a dum# terminal,

an intelligent terminal or a 4! A dum# terminal cannot store data

or do processing of its own 9t has the input and output device only

An intelligent terminal has the input and output device, can do

processing, #ut, cannot store data of its own $he dum# and the

intelligent terminal use the processing power and the storage

facility of the mainframe computer 6ost maor corporations usemainframes for #usiness activities 5ith mainframes, enterprises

are a#le to #ill millions of customers, prepare payroll for thousands

of employees, and manage thousands of items in inventory

Supercomputer

A supercomputer is the fastest, most powerful computer

% and the most e"pensive $he fastest supercomputers

are capa#le of processing more than one uadrillion

instructions in a single second

Applications reuiring comple", sophisticated

mathematical calculations use super computers @arge-

scale simulations and applications in medicine, aerospace,

automotive design, online #aning, weather forecasting,

nuclear energy research, and petroleum e"ploration use a

supercomputer

computer components and development

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