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Ayntachnbitninnannibbltncannbtn0norn1,nfournbitynltadnton16n(=24)ndifftrtntnnibblty:n0000,n0001,n0010,n0011,n0100,n0101,n
        0110,n0111,n1000,n1001,n1010,n1011,n1100,n1101,n1110,n1111.nThuy,nannibbltncanntxmrtyynannuobtrnbttwttnn0nandn15.nn
        AnytqutnctnofntightnbitynforoynanbStt.nAgain,nayntachnbitninnanbSttncannbtn0norn1,nnanbSttncanntxmrtyyn256n(=28)ndifftrtntn
        ytqutncty.nThuy,nanbSttniynuytdntontxmrtyynannuobtrnbttwttnn0nandn255.nnThtnbSttyncannbtnfurthtrngroumtdntonforon
        biggtrnunitynofnotoorS.nTabltn1.1nyhowyndifftrtntnunitynofnotoorS.n
                                   1nBit                   =    BinarSnDigit
                                   8nBity                  =    1nBStt

                                   1024nBStty              =    1KBn[KilonBStt]
                                   1024nKB                 =    1MBn[MtganBStt]

                                   1024nMB                 =    1GBn[GiganBStt]
                                   1024nGB                 =    1TBn[TtrranBStt]
                                   1024nTB                 =    1PBn[PttanBStt]

                                   1024nPB                 =    1EBn[ExanBStt]
                                   1024nEB                 =    1ZBn[ZtttanBStt]

                                   1024nZB                 =    1YBn[YottanBStt]
                                   1024nYB                 =    1nBrontonBStt
                                   1024nBrontobStt         =    1nGtomnBStt

                                                 Tabltn1.1:nUnitynofnMtoorS

        1.5.2 Types of Memory

        ThtnotoorSnunitnconyiytynofnthtnfollowingntSmtynofnotoorS:
        A. Primary Memory
        PrioarSnotoorSn(alyoncalltdnoainnotoorS)niynuytdntonytortndatanandninytructonyntonbtnmroctyytdnbSnthtn PU.nDatan
        andninytructonnoaSnbtnytortdn(writttnnintonotoorS)nandnrttritvtdn(rtadnfroonotoorS)nfornmroctyying.nnPrioarSn
        otoorSniynoainlSnofntwontSmty:
           ●   Random Access Memory (RAM)
        RAMniynanrandoonacctyynotoorSninnwhichndatancannbtnrtadnfroonandnwritttnnontonanSnrandoonotoorSnlocaton.nItniyn
        alyoncoooonlSnknownnaynoainnotoorSnornrtad/writtnotoorS.nAynthtnmrioarSnotoorSnytortyndatanandninytructonyn
        ayyociattdnwithnmrograoyncurrtntlSnbtingntxtcuttdnbSnthtn PU,nthtndataniynnotnytortdnmtroantntlS.nThtndatanandn
        inytructonynartnrttaintdninnthtnRAMnaynlongnaynthtncoomuttrnrtoainynconntcttdntonthtnmowtrnyummlS.nRAMnconttntyn
        artnloytnwhtnnthtnmowtrnyummlSniynywitchtdnoff.n o,nRAMnniynalyonknownnaynvolatltnotoorS.
           ●   Read Only Memory (ROM)
        DataniynwritttnninnRtadnOnlSnMtoorSn(ROM)nuyingnymtcialiytdnhardwart.nnROMniynannon-volatltnotoorSnthatnytortynthtn
        datanmtroantntlS,ni.t.nthtnconttntynartnnotnloytntvtnnwhtnnthtnmowtrnyummlSniynturntdnoff.nThtndatanacctyynfroonROMn
        iyncoomaratvtlSnylowtrnayncoomartdntonRAM.nnDatanandninytructonynytortdninnROMnatnthtntotnofnoanufacturingnartn
        rartlSntonbtnchangtd.nAnROMnvariant,nErayabltnPrograooabltnROMn(EPROM),nallowyndataninnEPROMntonbtnovtrwritttnn
        uyingnanymtcialiytdnhardwartnotchaniyo.nWhtnnancoomuttrniynywitchtdnon,ninytructonyninnnROMnytartngtttingntxtcuttdn
        tonoaktnthtncoomuttrnrtadSnfornuyt.nThtnmrograoninnROMnthatninitattynthtnmroctyynofnbringingnumnthtncoomuttrnforn
        uytniyncalltdnthtnbootytramnmrograo.n



               Various types of ROM are PROM, EPROM, and EEPROM.


          14   Touchpad Informatics Practices-XI
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