introduction to communication technology

8/14/2019 introduction to communication technology

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UNESCO ICTLIP Module 1. Lesson 2 1

CommunicationTechnologies

Lesson 2. How do computers work?



UNESCO ICTLIP Module 1. Lesson 22

Rationale

The lesson will introduce you to thecomputer. our !nowled"e #$out theelements o% the computer #nd howthey wor! will en#$le you to e#silyunderst#nd the lessons on h#rdw#re&

so%tw#re #nd networ!s.



UNESCO ICTLIP Module 1. Lesson 2'

Scope(h#t is # computer)(h#t #re the elements o% # computer system)(h#t #re the di%%erent types o% computer systems)(h#t #re the components o% # d#t# processin"cycle)(h#t is the role o% # computer in the d#t#processin" cycle)

(h#t #re some trends in the de*elopment o%computers)



UNESCO ICTLIP Module 1. Lesson 2+

Learning Outcomes,y the end o% this lesson& you should $e #$le to-

escri$e how computers process in%orm#tionList the elements o% # computer systemIdenti%y the di%%erent types o% computersystems #nd their usesE/pl#in the d#t# processin" cycle

e%ine the role o% computers in the d#t#processin" cycle,e #w#re o% de*elopment trends in ICT



UNESCO ICTLIP Module 1. Lesson 2 5

What is a computer?

0 computer is # m#chine with electronic#nd electromech#nic#l p#rts. It ispro"r#mm#$le #nd is c#p#$le o%per%ormin" the %ollowin" %unctions-

0ccept d#t# inputProcess d#t#3ener#te output in%orm#tion )

Store d#t#4in%orm#tion5etrie*e4send d#t#4in%orm#tion




Development of computers

The $e"innin" o% the commerci#l computer#"e $e"#n on 7une 1+& 1891 with thedeli*ery o% UNI:0C;;Uni*ers#l 0utom#ticComputer to the U.S. ,ure#u o% CensusPrior to this& howe*er& Ch#rles ,#$$#"ein*ented the i%%erence En"ine #ndconcei*ed o% #nother m#chine c#lled

0n#lytic#l En"ine. The l#tter h#d #ll thecomponents o% the computer input& output&processin" #nd stor#"e. ,#$$#"e is c#lledthe %#ther o% computers.


http://slidepdf.com/reader/full/introduction-to-communication-technology 7/22UNESCO ICTLIP Module 1. Lesson 2<

What are the so-calledcomputer generations?

=irst "ener#tion& 1891;189>- :#cuum tu$eswere used #s the intern#l computercomponents& punched c#rds #nd m#"netic

t#pes %or storin" d#t#& #nd m#chine l#n"u#"e%or pro"r#mmin".Second "ener#tion& 1898;186+- Tr#nsistorsrepl#ces *#cuum tu$es& #ssem$ly l#n"u#"e#nd hi"h le*el l#n"u#"es repl#ced m#chinel#n"u#"e& #nd the remo*#$le dis! p#c!repl#ced punched c#rds. Tr#nsistors en#$ledm#nu%#cturers to produce sm#ller computers.


http://slidepdf.com/reader/full/introduction-to-communication-technology 8/22UNESCO ICTLIP Module 1. Lesson 2>

Generations continued!Third "ener#tion& 1869;18<?- Inte"r#ted

circuits ;;complete electronic circuits on #silicon chip were de*eloped. ICs led to theproduction o% e*en sm#ller computers c#lledmini computers. So%tw#re $ec#me moresophistic#ted #nd inter#cti*e processin"possi$le=ourth "ener#tion& 18<1;present. Themicroprocessor or computer on # chip w#sde*eloped. This m#de PCs& #nd other

#pplic#tions possi$le c#lcul#tors& $#n!in"&...=i%th "ener#tion& present #nd $eyond ; recent#nd emer"in" technolo"ies& i.e. *oicereco"nition& #rti%ici#l intelli"ence& neur#lsystems& @u#ntum computers&A


http://slidepdf.com/reader/full/introduction-to-communication-technology 9/22UNESCO ICTLIP Module 1. Lesson 28

"lements of a computers#stem

1. People ; the most import#nt p#rt #nd$ene%ici#ry o% # computer system&"ener#lly c#te"oriBed #s either end;usersor de*elopers2. Procedures ; #re descriptions o% howthin"s #re done& i.e. m#nu#ls&document#tions& A'. #t#4In%orm#tion ; r#w %#cts d#t# #ndprocessed d#t# in%orm#tion th#t #re usedto produce the desired result


http://slidepdf.com/reader/full/introduction-to-communication-technology 10/22UNESCO ICTLIP Module 1. Lesson 21?

"lements of a computers#stem

+. #rdw#re ; the physic#l element o% #computer system c#te"oriBed #ccordin" tothe $#sic oper#tions they per%orm- input&processin"& output& stor#"e #ndcommunic#tions.9. So%tw#re ; pro*ides the step $y stepinstructions th#t tell the computer wh#t to

do. 3ener#lly so%tw#re is di*ided into systemso%tw#re #nd #pplic#tion so%tw#re.6. Communic#tions ; re%ers to the electronictr#ns%er o% d#t# %rom one pl#ce to #nother




What are the differentt#pes of computer

s#stems?In "ener#l& computers #re sorted#ccordin" to physic#l siBe #nd

processin" power.The di%%erent types #re- SupercomputerM#in%r#me& Minicomputer&Microcomputer es!top&L#ptop&Note$oo!& P#lmtop & Microcontroller




$o% is datarepresented in thecomputer?Computers represent d#t# #s two;st#tesystems. This me#ns th#t the computerreco"niBes only two num$ers& ? #nd 1.

L#r"er num$ers& letters #nd speci#lch#r#cters #re %ormed usin" com$in#tionso% ? #nd 1. E#ch o% these two num$ers isc#lled # bit %rom the words b in#ry di" it.The com$in#tion o% $its to %orm me#nin"%ulch#r#cters or num$ers is c#lled # byte.



UNESCO ICTLIP Module 1. Lesson 21'

What coding schemes areused to form meaningful

&#tes of data?There #re usu#lly > $its in # $yte. Thecodin" scheme 0SCII 0s;!ey #nd

0SCII;> or e/tended 0SCII h#s $een#dopted #s # st#nd#rd $y the US"o*ernment #nd $y computerm#nu%#cturers.

0SCII c#n h#*e 12> com$in#tions o% <$its e#ch while 0SCII;> c#n h#*e #sm#ny #s 1296 com$in#tions



UNESCO ICTLIP Module 1. Lesson 21+

$o% is data processed intoinformation?

Input Output

0uthor Title

ImprintSu$DectC#ll No.

0ccession No.

C#t#lo" 5ecord

C#rd C#t#lo"

Process

C#t#lo"in"Process =ilin"

Process

#t# In%orm#tion

Stor#"e




The Information'rocessing C#cle

'rocessData

Input

DocumentStored Data

Output

(e% Document




What is the role ofcomputers in the

information c#cle? 0ccept d#t# throu"h input de*ices

Process d#t# usin" microprocessorsStore d#t# %or inter#cti*e use in the50M #nd %or lon"er periods o% stor#"e

in the 5OM #nd h#rd dis!sOutput d#t# throu"h output de*ices.



UNESCO ICTLIP Module 1. Lesson 21<

What are the advantagesof using computers fordata processing?

=#ster d#t# input& processin" #ndretrie*#lTireless;;c#n wor! 2+ hours # d#y& <d#ys # wee!Less prone to error

Produce output re@uirements e#silyCould send #nd retrie*e d#t# %romother computers i% in # networ!



UNESCO ICTLIP Module 1. Lesson 21>

What are somedisadvantages of using

computers?5e@uire s!illed m#npower %or desi"n #ndpro"r#mmin" #nd d#t# encodin"5e@uire electricity5e@uire #ir conditionin" %or non;stopwor!E/pensi*e to #c@uire #nd m#int#in

5e@uire %re@uent up"r#de due to %#stde*elopments in h#rdw#re #nd so%tw#re5e@uire re"ul#r st#%% tr#inin"




What are some generaltrends in computers?

Moore s L#w- Computin" power dou$les#ppro/im#tely e*ery 1> months=#ster processors,i""er stor#"e c#p#city,i""er memorySt#nd #loneFFFNetwor!FFF istri$uti*ecomputin"So%tw#re $lo#tLower cost



UNESCO ICTLIP Module 1. Lesson 22?

What are some generaltrends in hard%are?

ownsiBin"-M#in%r#me FFF PCFFPoc!et PC

5i"ht siBin"

Incre#sin" memory-50M 1M, to #t le#st 296 M,

Incre#sin" stor#"e-

#rd dis! 1? M, to 2? 3,ecre#sin" costIncre#sin" processor speed-

PC GT to Pentium +




What are some general

trends in soft%are?More sophistic#ted so%tw#re

,i""er stor#"e re@uirement,i""er memory re@uirementMore user %riendly-

OS to (indows



UNESCO ICTLIP Module 1 Lesson 222

Conclusion

Computers #re reli#$le #nd e%%icienttools %or d#t# processin" #ndin%orm#tion retrie*#l.There #re#d*#nt#"es #nd dis#d*#nt#"es inusin" them. The e%%iciency o% thesetools is dependent on thespeci%ic#tions o% the computerh#rdw#re& the so%tw#re& d#t#$#sedesi"n #nd the user.

introduction to communication technology

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