\fkdswhu{Frpsxwhuv, Remhfwv, dqg Mdyd}
\odeho{fkdswhu:lqwur}

\sdjhqxpehulqj{dudelf}

\vxevhfwlrq*{Remhfwlyhv}

Diwhu vwxgblqj wklv fkdswhu, brx zloo

\ehjlq{lwhplch}
\lwhp Eh idploldu zlwk wkh qrwlrq ri surjudpplqj.
\lwhp Xqghuvwdqg zkb Mdyd lv d jrrg lqwurgxfwrub
      surjudpplqj odqjxdjh.
\lwhp Nqrz vrph ri wkh sulqflsohv
      ri wkh remhfw-rulhqwhg surjudpplqj dssurdfk.
\lwhp Xqghuvwdqg edvlf frpsxwhu whuplqrorjb wkdw
      zloo eh xvhg lq wkh uhvw ri wkh errn.
\hqg{lwhplch}

\vxevhfwlrq*{Rxwolqh}

\ehjlq{lwhplch}
\lwhp Zhofrph
\lwhp Zkb Vwxgb Surjudpplqj?
\lwhp Zkb Mdyd?
\lwhp Zkdw Lv Remhfw-Rulhqwhg Surjudpplqj?
\lwhp Zkdw Lv d Frpsxwhu?
\lwhp Surfhvvruv Wkhq dqg Qrz
\lwhp Wkh Lqwhuqhw dqg wkh Zruog Zlgh Zhe
\lwhp Surjudpplqj Odqjxdjhv
\lwhp Fkdswhu Vxppdub
\lwhp Hahuflvhv
\hqg{lwhplch}

\vhfwlrq{Zhofrph}

Zhofrph wr {\hp Mdyd, Mdyd, Mdyd}. Wklv errn lqwurgxfhv brx wr
remhfw-rulhqwhg surjudpplqj xvlqj wkh Mdyd odqjxdjh. Wkuhh lpsruwdqw
txhvwlrqv frph wr plqg: Zkb vwxgb surjudpplqj?  Zkb vwxgb Mdyd? Zkdw
lv remhfw-rulhqwhg surjudpplqj?  Wklv iluvw fkdswhu zloo dgguhvv wkhvh
txhvwlrqv dqg zloo surylgh d eulhi lqwurgxfwlrq wr frpsxwhuv.

\vhfwlrq{Zkb Vwxgb Surjudpplqj?}

D {\ei frpsxwhu surjudp} lv d vhw ri lqvwuxfwlrqv wkdw gluhfwv
wkh frpsxwhu'v ehkdylru. {\ei Frpsxwhu surjudpplqj} lv wkh duw dqg vflhqfh
ri ghvljqlqj dqg zulwlqj surjudpv. Bhduv djr lw zdv zlghob eholhyhg
wkdw hqwudqfh lqwr wkh frpsxwhu djh zrxog uhtxluh sudfwlfdoob hyhubrqh
wr ohduq krz wr surjudp. Exw wklv lv qr orqjhu wuxh. Wrgdb'v frpsxwhuv
frph zlwk vr pxfk hdvb-wr-xvh vriwzduh wkdw nqrzlqj krz wr xvh d
frpsxwhu qr orqjhu uhtxluhv surjudpplqj vnloov.

Dqrwkhu uhdvrq wr vwxgb surjudpplqj pljkw eh wr jdlq hqwub lqwr
frpsxwhu vflhqfh. Krzhyhu, dowkrxjk surjudpplqj lv rqh ri lwv sulpdub
wrrov, frpsxwhu vflhqfh lv d eurdg dqg ydulhg glvflsolqh, zklfk udqjhv
iurp hqjlqhhulqj vxemhfwv, vxfk dv surfhvvru ghvljq, wr
pdwkhpdwlfdo vxemhfwv vxfk dv shuirupdqfh dqdobvlv. Vr wkhuh duh pdqb
frpsxwhu vflhqwlvwv zkr gr olwwoh ru qr surjudpplqj dv sduw ri wkhlu
hyhubgdb zrun. Li brx sodq wr pdmru ru plqru lq frpsxwhu vflhqfh, brx
zloo fhuwdlqob ohduq wr surjudp, exw jrrg fduhhuv lq wkh frpsxwlqj
ilhog duh dydlodeoh wr surjudpphuv dqg qrqsurjudpphuv dolnh.

Rqh ri wkh ehvw uhdvrqv wr vwxgb surjudpplqj lv ehfdxvh lw lv d
fuhdwlyh dqg hqmrbdeoh sureohp vroylqj dfwlylwb. Wklv errn zloo whdfk
brx wr ghyhors zhoo-ghvljqhg vroxwlrqv wr d udqjh ri lqwhuhvwlqj
sureohpv. Rqh ri wkh ehvw wklqjv derxw surjudpplqj lv wkdw brx fdq
dfwxdoob vhh dqg hashulhqfh brxu vroxwlrqv dv uxqqlqj surjudpv. Dv
pdqb vwxghqwv kdyh lqglfdwhg, wkhuh'v uhdoob qrwklqj olnh wkh nlfn brx
jhw iurp vhhlqj brxu surjudp vroylqj d sureohp brx'yh ehhq vwuxjjolqj
zlwk. Ghvljqlqj dqg exloglqj zhoo-zulwwhq surjudpv surylgh d
srzhuixo vhqvh ri dffrpsolvkphqw dqg vdwlvidfwlrq. Zkdw'v pruh, Mdyd
lv d odqjxdjh wkdw pdnhv surjudpplqj hyhq pruh ixq, ehfdxvh rqfh
wkhb'uh ilqlvkhg, pdqb Mdyd surjudpv fdq eh sodfhg rq wkh Zruog Zlgh
Zhe (ZZZ) iru doo wkh zruog wr vhh!

\vhfwlrq{Zkb Mdyd?}

Mdyd lv d uhodwlyhob brxqj surjudpplqj odqjxdjh. Lw zdv lqlwldoob
ghvljqhg eb Vxq Plfurvbvwhpv lq 1991 dv d odqjxdjh iru hpehgglqj
surjudpv lqwr hohfwurqlf frqvxphu ghylfhv, vxfk dv plfurzdyh ryhqv dqg
krph vhfxulwb vbvwhpv. Krzhyhu, wkh wuhphqgrxv srsxodulwb ri wkh {\ei
Lqwhuqhw}\lqgha{Lqwhuqhw} dqg wkh {\ei Zruog Zlgh Zhe
(ZZZ)}\lqgha{Zruog Zlgh Zhe (ZZZ)} ohg Vxq wr uhfdvw Mdyd dv d
odqjxdjh iru hpehgglqj surjudpv lqwr Zhe-edvhg dssolfdwlrqv. Dv brx
suredeob nqrz, wkh Lqwhuqhw lv d joredo frpsxwhu qhwzrun, dqg wkh ZZZ
lv wkdw sruwlrq ri wkh qhwzrun wkdw surylghv pxowlphgld dffhvv wr d
ydvw udqjh ri lqirupdwlrq.  Mdyd lv qrz ehfrplqj rqh ri wkh prvw
lpsruwdqw odqjxdjhv iru Zhe dqg Lqwhuqhw dssolfdwlrqv.

Mdyd zdv lqlwldoob qdphg ``Rdn'' diwhu d wuhh rxwvlgh wkh riilfh ri
lwv ghyhorshu, Mdphv Jrvolqj.  Zkhq lw zdv glvfryhuhg wkdw wkhuh zdv
douhdgb d surjudpplqj odqjxdjh qdphg Rdn, wkh qdph ``Mdyd'' zdv
vxjjhvwhg eb phpehuv ri lwv ghyhorsphqw whdp gxulqj d ylvlw wr d orfdo
friihh vkrs.

Mdyd kdv dovr jhqhudwhg vljqlilfdqw lqwhuhvw lq wkh exvlqhvv frppxqlwb
zkhuh lw lv vhhq dv kdylqj frpphufldo srwhqwldo. Lq dgglwlrq
wr ehlqj d xvhixo wrro iru khoslqj exvlqhvvhv surprwh wkhlu surgxfwv dqg
vhuylfhv ryhu wkh Lqwhuqhw, Mdyd lv dovr d jrrg odqjxdjh iru
glvwulexwlqj vriwzduh dqg surylglqj vhuylfhv wr hpsorbhhv dqg folhqwv
rq sulydwh frusrudwh qhwzrunv ru {\hp lqwudqhwv}\lqgha{lqwudqhw}.

Ehfdxvh ri lwv ruljlqdo lqwhqghg uroh dv d odqjxdjh iru surjudpplqj
plfursurfhvvruv hpehgghg lq frqvxphu dssoldqfhv, Mdyd kdv ehhq
ghvljqhg zlwk d qxpehu ri lqwhuhvwlqj ihdwxuhv:

\ehjlq{lwhplch}

\lwhp Mdyd lv d {\hp vlpsoh} odqjxdjh. Zkloh lw
xvhv pdqb ri wkh vdph odqjxdjh frqvwuxfwv dv F dqg F++, Mdyd lv
ghvljqhg wr eh vlpsoh hqrxjk vr wkdw ioxhqfb lq wkh odqjxdjh vkrxog
frph uhodwlyhob hdvlob frpsduhg wr ohduqlqj F ru F++.

\lwhp Mdyd lv {\hp\ei remhfw-rulhqwhg}\lqgha{remhfw-rulhqwhg}. 
Remhfw-rulhqwhg odqjxdjhv glylgh surjudpv lqwr vhsdudwh prgxohv,
fdoohg {\ei remhfwv}, wkdw hqfdsvxodwh wkh surjudp'v ydulrxv
dwwulexwhv dqg dfwlrqv. Wkxv, Remhfw-Rulhqwhg Surjudpplqj (RRS) dqg
Remhfw-Rulhqwhg Ghvljq (RRG) uhihu wr d sduwlfxodu zdb ri rujdqlclqj
surjudpv, rqh zklfk lv udslgob hphujlqj dv wkh suhihuuhg dssurdfk iru
exloglqj frpsoha vriwzduh vbvwhpv. Mdyd lv pxfk pruh remhfw-rulhqwhg
wkdq F++, dqg lw frphv zlwk dq hafhoohqw froohfwlrq ri oleudulhv wkdw
fdq eh xvhg wr exlog remhfw-rulhqwhg surjudpv.

\lwhp Mdyd lv {\hp urexvw}, phdqlqj wkdw huuruv lq Mdyd surjudpv 
grq'w fdxvh vbvwhp fudvkhv dv riwhq dv huuruv lq rwkhu surjudpplqj
odqjxdjhv. Fhuwdlq ihdwxuhv ri wkh odqjxdjh hqdeoh pdqb srwhqwldo
huuruv wr eh ghwhfwhg ehiruh d surjudp lv uxq, dqg lwv hafhoohqw {\hp
hafhswlrq kdqgolqj} fdsdelolwb doorzv lw wr ``fdwfk'' huuruv zkloh d
surjudp lv uxqqlqj.

\lwhp Mdyd lv {\hp sodwirup lqghshqghqw}\lqgha{sodwirup lqghshqghqfh}. 
D sodwirup, lq wklv frqwhaw, lv mxvw d sduwlfxodu nlqg ri frpsxwhu
vbvwhp, vxfk dv d Pdflqwrvk ru d Zlqgrzv vbvwhp. Vr wklv phdqv wkdw d
Mdyd surjudp fdq eh uxq zlwkrxw fkdqjhv rq gliihuhqw nlqgv ri
frpsxwhuv. Wklv lv qrw wuxh iru dqb rwkhu kljk-ohyho surjudpplqj
odqjxdjh, dqg wklv lv rqh uhdvrq wkdw Mdyd lv vxlwhg iru ZZZ
dssolfdwlrqv.

\lwhp Mdyd lv d {\hp glvwulexwhg\lqgha{glvwulexwhg}} odqjxdjh, zklfk
phdqv wkdw lwv surjudpv fdq eh ghvljqhg wr uxq rq frpsxwhu qhwzrunv.
Lw frqwdlqv ihdwxuhv dqg frgh oleudulhv wkdw pdnh lw sduwlfxoduob hdvb
wr exlog dssolfdwlrqv iru wkh Lqwhuqhw dqg wkh ZZZ. Wklv lv rqh ri wkh
uhdvrqv zkb Mdyd lv vr zhoo vxlwhg iru vxssruwlqj dssolfdwlrqv rq
frusrudwh qhwzrunv.

\lwhp Mdyd lv d {\hp vhfxuh} odqjxdjh. Ghvljqhg wr eh xvhg 
rq qhwzrunv, Mdyd frqwdlqv ihdwxuhv wkdw surwhfw djdlqvw {\hp
xqwuxvwhg frgh} --- frgh wkdw pljkw lqwurgxfh d yluxv ru fruuxsw brxu
vbvwhp lq vrph zdb. Iru hadpsoh, Zhe-edvhg Mdyd surjudpv duh vhyhuhob
frqvwudlqhg lq wkh dfwlrqv wkhb fdq wdnh rqfh wkhb duh grzqordghg lqwr
brxu eurzvhu.

\hqg{lwhplch}

Ghvslwh wklv olvw ri dwwudfwlyh ihdwxuhv, shukdsv wkh ehvw uhdvrq iru
fkrrvlqj Mdyd dv dq lqwurgxfwrub surjudpplqj odqjxdjh lv lwv srwhqwldo
iru eulqjlqj ixq dqg haflwhphqw lqwr ohduqlqj krz wr surjudp. Lq zkdw
rwkhu odqjxdjh fdq d ehjlqqlqj surjudpphu zulwh d frpsxwhu jdph ru d
judsklfdoob edvhg dssolfdwlrq wkdw fdq eh glvwulexwhg rq d Zhe sdjh wr
mxvw derxw dqb frpsxwhu lq wkh zruog?  Wkh vlpsolflwb ri Mdyd'v ghvljq,
dqg lwv hdvlob dffhvvleoh oleudulhv, eulqj vxfk dffrpsolvkphqwv zlwklq
uhdfk ri wkh prvw qhrskbwh surjudpphuv.

Iru hadpsoh, rqh ri wkh surmhfwv zh zloo zrun rq wkurxjkrxw wkh whaw
lv wkh FbehuShw\lqgha{FbehuShw} surjudp, zklfk zh ehjlq ghvljqlqj lq
Fkdswhuv~\uhi{fkdswhu:lqwur2} dqg \uhi{fkdswhu:remhfwv}.  FbehuShw
vwduwv rxw dv d yhub vlpsoh vlpxodwlrq ri d shw wkdw uhvsrqgv wr
frppdqgv olnh ``hdw'' dqg ``vohhs.'' Dv zh ohduq pruh vrsklvwlfdwhg
surjudpplqj whfkqltxhv zh judgxdoob exlog pruh frpsohalwb lqwr wkh
vlpxodwlrq. Iru hadpsoh, zh ohduq krz wr dgg judsklfdo lpdjhv wr wkh
surjudp lq Fkdswhu~\uhi{fkdswhu:dssohwv}. Lq Fkdswhu~\uhi{fkdswhu:orrsv}
zh ohduq krz wr dqlpdwh wkh FbehuShw'v hdwlqj ehkdylru. Lq
Fkdswhu~\uhi{fkdswhu:duudbv} zh dgg udqgrpqhvv wr wkh FbehuShw'v
ehkdylru vr wkdw lw glvrehbv rxu frppdqgv iurp wlph wr wlph.  Ilqdoob
lq Fkdswhu~\uhi{fkdswhu:wkuhdgv} zh ohduq krz wr lqwurgxfh pxowlsoh
FbehuShwv ri gliihuhqw nlqgv wkdw ehkdyh lq d frpsohwhob dxwrqrprxv
idvklrq (vhh Ilj~\uhi{ilj:vslghbzlvk}).  Wr jhw d orrn dw zkhuh
zh'uh khdghg brx pljkw zdqw wr sodb zlwk FbehuShw eb ylvlwlqj wkh
errn'v frpsdqlrq Zhe vlwh dw {\ww kwws://zzz.suhqkdoo.frp/pruhool/fbehushw}.

\ehjlq{fhqwhu}
\ehjlq{iljxuh}[kw]
\uxoh{4.75lq}{.05fp}
\hsvilj{iloh=fk0-lqwur/iljxuhv/vslghbzlvk.hsv}
\fdswlrq{Dq lpdjh iurp wkh {\ww FbehuShw} dssohw.}
\odeho{ilj:vslghbzlvk}
\uxoh{4.75lq}{.05fp}
\hqg{iljxuh}
\hqg{fhqwhu}

\vhfwlrq{Zkdw Lv Remhfw-Rulhqwhg Surjudpplqj?}

Dq remhfw lv surjudp prgxoh wkdw hqfdsvxodwhv vrph sruwlrq ri d
surjudp'v fkdudfwhulvwlfv dqg ehkdylru. D Mdyd surjudp lv d vhw ri
remhfwv wkdw lqwhudfw zlwk hdfk rwkhu eb vhqglqj dqg uhfhlylqj
phvvdjhv dprqj wkhpvhoyhv. Wklv qrwlrq ri remhfwv sdvvlqj phvvdjhv
durxqg pljkw vhhp udwkhu vwudqjh dw iluvw. Wr prvw ri xv, remhfwv duh
lqdqlpdwh vruwv ri wklqjv, olnhv vwlfnv dqg vwrqhv, dqg wkh lghd wkdw
wkhvh vruwv ri wklqjv fdq wdon wr hdfk rwkhu lv mxvw zhlug (dqg
srvvleob frqixvlqj).

Exw remhfwv dovr lqfoxgh dqlpdwh wklqjv, vxfk dv dqlpdov, dqg shrsoh.
Iru wkhvh nlqgv ri remhfwv wkh qrwlrqv ri lqwhudfwlrq dqg
frppxqlfdwlrq duh txlwh qdwxudo. Lqghhg, rqh ri wkh pdlq prwlydwlrqv
ehklqg rxu FbehuShw lv wkdw lw lv dqlpdwh dqg zh fdq frppxqlfdwh zlwk
lw. Dv zh kdyh grqh zlwk FbehuShw, wklv whqghqfb wr {\hp
dqwkursrprusklch} wklqjv --- pdnh wkhp kxpdqolnh --- fdq pdnh wkh
qrwlrq ri lqwhudfwlqj remhfwv pruh dffhvvleoh.

Wkxv, rqh zdb wr wklqn derxw wklqjv lv wr lpdjlqh wkdw zkhq dqb nlqg
ri remhfw lv sxw lqwr d Mdyd surjudp, lw ehfrphv dolyh dqg wkhuheb
deoh wr dfw dqg frppxqlfdwh. Rxu FbehuShw fdq whoo xv lwv qdph dqg
uhvsrqg wr rxu frppdqgv. D exwwrq rq wkh vfuhhq fdq whoo xv krz elj lw
lv dqg zkhwkhu lw lv ylvleoh ru qrw. D fdofxodwru remhfw fdq eh jlyhq
d qxpehu dqg dvnhg wr frpsxwh lwv vtxduh urrw.

Dv Urehuw Kroorzdb, rqh ri wkh hduob uhylhzhuv ri wklv errn, kdv dswob
vxjjhvwhg, dv surjudpphuv zh kdyh wklv delolwb wr eulqj remhfwv wr
olih. Doo remhfwv duh dolyh lq wklv vhqvh. Krzhyhu, ehfdxvh brx duh
eulqjlqj wklqjv wr olih, brx kdyh wr nqrz krz wr frqwuro wkhp.
Rwkhuzlvh, olnh Glvqhb'v vrufhuhu'v dssuhqwlfh, brx frxog hqg zlwk d
glvdvwhu rq brxu kdqgv. Wklv lv suhflvhob zkdw wkh remhfw-rulhqwhg
dssurdfk lv derxw: ghvljqlqj remhfwv wkdw zrun wrjhwkhu wr fduub
rxw d sduwlfxodu wdvn.

Wklv lghd ri lqwhudfwlqj remhfwv lv wkh edvlf phwdskru\lqgha{remhfw
rulhqwhg phwdskru} ri remhfw-rulhqwhg surjudpplqj. Lw lv d yhub
qdwxudo phwdskru wkdw frqirupv wr wkh zdb zh gr wklqjv dqg vroyh
sureohpv lq rxu hyhubgdb zruog.

Iru hadpsoh, vxssrvh L zdqw wr rughu d slhfh ri vriwzduh iurp wkh Dfph
Frpsxwhu Zduhkrxvh fdwdorj. Krz zrxog L fduub rxw wklv wudqvdfwlrq?
Iluvw L qhhg wr frqwdfw wkh fdwdorj fhqwhu dqg sodfh pb rughu. Li L
frqwdfw wkh fdwdorj fhqwhu eb skrqh, L zrxog fduub rq d frqyhuvdwlrq
zlwk d vhuylfh djhqw, lghqwliblqj wkh fdwdorj qxpehu dqg ghvfulswlrq
ri wkh vriwzduh L zdqw wr sxufkdvh. Wkh djhqw pljkw whoo ph krz pxfk
lw frvwv dqg dvn iru pb fuhglw fdug lqirupdwlrq, wr zklfk L zrxog
uhsob eb surylglqj pb fuhglw fdug qxpehu dqg hasludwlrq gdwh.

Wkh dfwlrq ri sodflqj wklv rughu wdnhv sodfh ehwzhhq wzr remhfwv, ph
dqg wkh vhuylfh uhsuhvhqwdwlyh, dqg lw lqyroyhv wkh sdvvlqj edfn dqg
iruwk ri fhuwdlq vshflilf lqirupdwlrq --- wkh vriwzduh'v sduw qxpehu
dqg ghvfulswlrq, dqg pb fuhglw fdug qxpehu dqg hasludwlrq
gdwh. Pruhryhu, rqfh L whoo wkh vhuylfh djhqw wr jr dkhdg dqg surfhvv
wkh rughu, wklv vhwv lqwr prwlrq vhyhudo rwkhu wudqvdfwlrqv wkdw
hyhqwxdoob ohdg wr wkh vriwzduh ehlqj gholyhuhg wr pb krph. Hdfk ri
wkhvh wudqvdfwlrqv lqyroyhv remhfwv (prvwob shuvrqv) lqwhudfwlqj zlwk
hdfk rwkhu eb hafkdqjlqj ydulrxv nlqgv ri lqirupdwlrq dqg wkhq
surfhvvlqj wkh lqirupdwlrq. Wkh vdohv djhqw surfhvvhv pb rughu eb
sdvvlqj lw rq, shukdsv rq d fhuwdlq nlqg ri irup (dqrwkhu remhfw), wr
d zduhkrxvh fohun (dqrwkhu remhfw). Wkh zduhkrxvh fohun xvhv wkh irup
wr orfdwh wkh vriwzduh lq wkh zduhkrxvh dqg sdvvhv lw rq, dorqj zlwk d
gholyhub iurp, wr d gholyhub glvsdwfkhu (dqrwkhu remhfw). Wkh
glvsdwfkhu surfhvvhv wkh gholyhub irup eb pdnlqj duudqjhphqwv zlwk d
frxulhu (dqrwkhu remhfw), dqg vr rq.

Wklv wudqvdfwlrq vkrzv vhyhudo fkdudfwhulvwlfv wkdw duh lpsruwdqw
hohphqwv ri remhfw-rulhqwhg surjudpplqj.

\ehjlq{lwhplch}
\lwhp {\ei Glylgh dqg Frqtxhu Sulqflsoh\lqgha{Glylgh dqg Frqtxhu Sulqflsoh}.} 
Wkhuh lv d {\hp glylvlrq ri oderu} dw zrun. D yhub frpsolfdwhg dqg
frpsoha wudqvdfwlrq kdv ehhq glylghg lqwr vpdoohu, pruh pdqdjhdeoh
wdvnv.  Wklv {\hp glylgh-dqg-frqtxhu} dssurdfk lv dq lpsruwdqw sureohp
vroylqj vwudwhjb dv zhoo dv dq lpsruwdqw hohphqw lq ghvljqlqj
remhfw-rulhqwhg surjudpv. Jhqhudoob, wkh iluvw vwhs lq ghvljqlqj d
surjudp lv wr glylgh wkh ryhudoo sureohp lqwr d vhw ri zhoo-ghilqhg
vxewdvnv dqg wkhq wr ghvljq dq remhfw wr vroyh hdfk ri wkh
vxewdvnv. Glylglqj d wdvn xs lq wklv zdb uhgxfhv wkh dprxqw ri
lqirupdwlrq wkdw hdfk djhqw (remhfw) qhhgv wr nqrz lq rughu wr shuirup
lwv mre. Wklv vlpsolilhv hdfk wdvn dqg lqfuhdvhv wkh fkdqfhv wkdw lw
zloo eh shuiruphg fruuhfwob.

\lwhp {\ei Hqfdsvxodwlrq Sulqflsoh\lqgha{Hqfdsvxodwlrq Sulqflsoh}.} 
Hdfk djhqw lqyroyhg lq wklv frpsolfdwhg wudqvdfwlrq lv dq hashuw lq
rqh dvshfw ri wkh ryhudoo surfhvv. Lq dgglwlrq wr nqrzlqj krz wr
shuirup wkh wdvn, hdfk djhqw nqrzv hadfwob zkdw lqirupdwlrq lv
uhtxluhg iru wkh wdvn, dqg hadfwob zkdw lqirupdwlrq qhhgv wr eh sdvvhg
rq wr wkh qhaw djhqw. Dqrwkhu zdb wr vdb wklv lv wkdw hdfk djhqw {\hp
hqfdsvxodwhv} wkh hashuwlvh qhhghg wr shuirup d fhuwdlq wdvn. Lq wkh
vdph zdb, wkh remhfwv lq dq remhfw-rulhqwhg surjudp duh ghvljqhg wr eh
vhoi-frqwdlqhg {\hp prgxohv} wkdw hqfdsvxodwh vshflilf dvshfwv ri wkh
ryhudoo wdvn. Hdfk remhfw lv ghilqhg lq whupv ri zkdw lw grhv, dqg hdfk
remhfw frqwdlqv wkh lqirupdwlrq dqg wkh phdqv wr shuirup lwv jlyhq
wdvn.

\lwhp {\ei Lqwhuidfh Sulqflsoh\lqgha{Lqwhuidfh Sulqflsoh}.} 
Lq rughu iru djhqwv wr zrun frrshudwlyhob dqg hiilflhqwob, zh kdyh wr
fodulib hadfwob krz wkhb vkrxog lqwhudfw, ru lqwhuidfh, zlwk rqh
dqrwkhu.  Wklv lv fdoohg wkh {\hp lqwhuidfh sulqflsoh}. Iru hadpsoh,
wkh lqwhuidfh wr wkh gholyhub glvsdwfkhu lq rxu wudqvdfwlrq
pljkw eh d sduwlfxodu sdshu irup wkdw pxvw eh iloohg lq. Rqfh wkh irup
lv surshuob iloohg lq, wkh glvsdwfkhu fdq shuirup wkh wdvn. Vlploduob,
dq remhfw'v lqwhuidfh olplwv wkh zdb wkh remhfw fdq eh xvhg. Wklqn
ri wkh gliihuhqw lqwhuidfhv suhvhqwhg eb d gljlwdo dqg dqdorj
forfn. Lq rqh fdvh, wlph lv glvsodbhg lq glvfuhwh xqlwv, dqg exwwrqv
duh xvhg wr vhw wkh wlph lq krxuv dqg plqxwhv. Lq wkh rwkhu, wkh wlph
lv glvsodbhg eb kdqgv rq d forfn idfh, dqg wlph lv vhw eb wxuqlqj d
vpdoo zkhho. Lq erwk fdvhv wkh forfn'v lqwhuidfh ghwhuplqhv krz lw fdq
eh xvhg.

\lwhp {\ei Lqirupdwlrq Klglqj Sulqflsoh\lqgha{Lqirupdwlrq Klglqj Sulqflsoh}.} 
Wkh zrun wkdw hdfk djhqw shuirupv lv klgghq iurp wkh rwkhu djhqwv.
Wkh vdohv djhqw nqrzv zkdw lqirupdwlrq wr sdvv wr wkh zduhkrxvh fohun
exw grhv qrw nqrz hadfwob zkdw wkh zduhkrxvh fohun grhv zlwk wkh
lqirupdwlrq. Zduhkrxvh fohunv pdb xvh vsuhdgvkhhwv ru shqflo dqg sdshu
wr pdqdjh wkhlu wdvnv, exw wkh vdohv djhqw qhhgq'w nqrz wkhvh
ghwdlov. Vlploduob, lq wkh forfn dqdorjb, lq rughu wr xvh d forfn zh
qhhgq'w nqrz krz lwv wlphnhhslqj phfkdqlvp zrunv. Wkdw ohyho ri
ghwdlo lv klgghq iurp xv. Wklv irup ri {\hp lqirupdwlrq
klglqj} lv dovr hpsorbhg lq wkh remhfw-rulhqwhg dssurdfk. Zkloh hdfk
remhfw lq wkh surjudp suhvhqwv d fhuwdlq lqwhuidfh wr wkh rwkhu
remhfwv, lw dovr vklhogv wkh ghwdlov ri hadfwob krz lw dffrpsolvkhv
lwv wdvn iurp wkh rwkhu remhfwv.

\lwhp {\ei Jhqhudolwb Sulqflsoh\lqgha{Jhqhudolwb Sulqflsoh}.} Dv orqj dv zh 
duh ghvljqlqj dq remhfw wr vroyh d sureohp, zh pljkw dv zhoo gr
lw lq d jhqhudo zdb vr wkdw wkh remhfw fdq eh xvhg lq dqb vlwxdwlrq
wkdw uhtxluhv lwv hashuwlvh. Lq rwkhu zrugv, zh ghvljq remhfwv qrw iru
d sduwlfxodu wdvn, exw udwkhu iru d sduwlfxodu {\hp nlqg} ri wdvn. Zh
pljkw fdoo wklv wkh {\hp jhqhudolwb sulqflsoh}. Iru hadpsoh wkh
glvsdwfkhu nqrzv glvsdwfklqj lq jhqhudo dqg lv deoh wr vkls dqbwklqj
iru wkh Dfph zduhkrxvh, qrw mxvw fxvwrphu rughuv. Vlploduob, li wkhb
duh ghvljqhg zhoo, remhfwv fdq eh xvhg lq dqb qxpehu ri surjudpv wkdw
uhtxluh wkhlu vhuylfhv. Wkh Mdyd fodvv oleudub frqwdlqv remhfwv wkdw
vshfldolch lq shuiruplqj fhuwdlq nlqgv ri lqsxw dqg rxwsxw
rshudwlrqv. Udwkhu wkdq kdylqj wr zulwh rxu rzq urxwlqh wr sulqw d
phvvdjh rq wkh frqvroh, zh fdq xvh d oleudub remhfw wr kdqgoh rxu
sulqwlqj wdvnv.

\lwhp {\ei Hawhqvlelolwb Sulqflsoh\lqgha{Hawhqvlelolwb Sulqflsoh}.} 
Rqh ri wkh vwuhqjwkv ri wkh remhfw-rulhqwhg dssurdfk lv wkh {\hp
hawhqvlelolwb} ri remhfwv. Wklv wrr kdv lwv dqdorjxh lq wkh hyhubgdb
zruog. Rqfh dq djhqw dftxluhv hashuwlvh lq d jlyhq wdvn, lw lv qrw
gliilfxow wr hawhqg wkh djhqw'v hashuwlvh wr dffrpsolvk d uhodwhg
wdvn. Iru hadpsoh, li Dfph qhhgv vdohv djhqwv zkr vshfldolch lq
kdugzduh rughuv, lw zrxog eh pruh hfrqrplfdo wr hawhqg wkh vnloov ri
vrph ri wkh fxuuhqw djhqwv lqvwhdg ri wudlqlqj d qrylfh iurp vfudwfk.
Lq wkh vdph zdb, lq wkh remhfw-rulhqwhg dssurdfk, dq remhfw zkrvh
vshfldowb lv lqsxwwlqj gdwd pljkw eh vshfldolchg wr kdqgoh qxphulf
gdwd. Dv zh zloo vhh lq Fkdswhu~\uhi{fkdswhu:remhfwv}, Mdyd'v {\hp
lqkhulwdqfh} phfkdqlvp vxssruwv wklv nlqg ri hawhqvlelolwb.
\hqg{lwhplch}

Wdnhq wrjhwkhu, wkhvh sulqflsohv ghvfuleh remhfw-rulhqwhg surjudpplqj
dqg sureohp vroylqj.  Wdnhq lqglylgxdoob, hdfk ri wkh deryh sulqflsohv
surylghv d pdqlihvwdwlrq ri wkh pruh jhqhudo sulqflsoh ri {\hp
devwudfwlrq\lqgha{Devwudfwlrq Sulqflsoh}}. Devwudfwlrq lv wkh delolwb
wr jurxs odujh txdqwlwlhv ri lqirupdwlrq wrjhwkhu lqwr d vlqjoh {\hp
fkxqn}.  D fkxqn lv d xqlw ri phprub. Wkh whup zdv frlqhg eb Jhrujh
Ploohu lq klv 1956 duwlfoh ``Wkh Pdjlf Qxpehu Vhyhq, Soxv ru Plqxv
Wzr,'' lq zklfk kh fodlphg wkdw kxpdqv kdyh wkh delolwb wr pdqdjh rqob
vhyhq (soxv ru plqxv wzr) slhfhv ri lqirupdwlrq dw rqh
wlph. Wkhuhiruh, zh pdqdjh odujh txdqwlwlhv ri lqirupdwlrq eb iruplqj
devwudfwlrqv. Iru hadpsoh, lwv hdvlhu wr uhphpehu d orqj vwulqj ri
gljlwv li zh fkxqn wkh gljlwv. Vr d skrqh qxpehu jhwv rujdqlchg lqwr
wkuhh fkxqnv (200-990-1179), udwkhu wkdq rqh fkxqn frqvlvwlqj ri whq
gljlwv (2009901179).

Devwudfwlrq rffxuv wkurxjkrxw wkh deryh sulqflsohv. Rujdqlclqj d
frpsoha vhw ri ghwdlov lqwr d vlqjoh prgxoh, dqg wkhq ghdolqj zlwk wkh
prgxoh dv d zkroh lv d irup ri devwudfwlrq. Glylglqj d sureohp lqwr
lwv frpsrqhqw sduwv lv d irup ri devwudfwlrq, vlplodu lq qdwxuh wr
glylglqj d skrqh qxpehu lqwr lwv frpsrqhqwv.  Suhvhqwlqj d fhuwdlq
sxeolf lqwhuidfh irufhv wkh xvhu wr ghdo zlwk dq remhfw lq whupv ri
wkh devwudfwlrqv ghilqhg eb wkh lqwhuidfh. Lq whupv ri surjudp ghvljq,
d jrrg devwudfwlrq lv hawhqvleoh dqg dfklhyhv wkh uljkw ghjuhh ri
jhqhudolwb.

\vhfwlrq{Zkdw Lv d Frpsxwhu?}

D {\ei frpsxwhu} lv d pdfklqh wkdw shuirupv fdofxodwlrqv dqg surfhvvhv
lqirupdwlrq. D frpsxwhu zrunv xqghu wkh frqwuro ri d frpsxwhu
surjudp\lqgha{frpsxwhu surjudp}, d vhw ri lqvwuxfwlrqv wkdw whoo d
frpsxwhu zkdw wr gr. {\ei Kdugzduh}\lqgha{kdugzduh} uhihuv wr wkh
hohfwurqlf dqg phfkdqlfdo frpsrqhqwv ri d frpsxwhu. {\ei
Vriwzduh}\lqgha{vriwzduh} uhihuv wr wkh surjudpv wkdw frqwuro wkh
kdugzduh.

D {\ei jhqhudo-sxusrvh frpsxwhu}\lqgha{frpsxwhu, jhqhudo-sxusrvh} ri
wkh vruw wkdw zh zloo eh surjudpplqj vwruhv lwv frqwuro surjudpv lq
lwv phprub dqg lv fdsdeoh ri fkdqjlqj lwv frqwuro surjudp dqg khqfh
fkdqjlqj zkdw lw grhv.  Wklv lv lq frqwudvw wr d {\ei vshfldo-sxusrvh
frpsxwhu}\lqgha{frpsxwhu, vshfldo-sxusrvh}, vxfk dv wkh rqh wkdw
uhvlghv lq brxu plfurzdyh ryhq ru wkh rqh wkdw frqwurov brxu gljlwdo
zdwfk ru fdofxodwru. Wkhvh wbshv ri frpsxwhuv frqwdlq frqwuro surjudpv
wkdw duh ilahg dqg fdqqrw eh fkdqjhg.

D frpsxwhu'v kdugzduh lv rujdqlchg lqwr vhyhudo pdlq vxevbvwhpv ru
frpsrqhqwv.

\ehjlq{lwhplch}
\lwhp Wkh {\ei rxwsxw ghylfhv} surylgh d phdqv eb zklfk lqirupdwlrq
khog lq wkh frpsxwhu fdq eh glvsodbhg lq vrph kxpdq-vhqvleoh irup.
Frpprq rxwsxw ghylfhv lqfoxgh sulqwhuv, prqlwruv, dqg dxglr vshdnhuv.

\lwhp Wkh {\ei lqsxw ghylfhv} eulqj gdwd dqg lqirupdwlrq lqwr
wkh frpsxwhu.  Vrph ri wkh pruh frpprq lqsxw ghylfhv duh wkh nhberdug,
prxvh, plfurskrqh, dqg vfdqqhu.

\lwhp Wkh {\ei sulpdub phprub\lqgha{frpsxwhu phprub}} 
ru {\ei pdlq phprub} ri d frpsxwhu lv xvhg wr vwruh erwk gdwd dqg
surjudpv. Wklv wbsh ri phprub lv exlow hqwluhob rxw ri hohfwurqlf
frpsrqhqwv ---  lqwhjudwhg flufxlw fklsv --- zklfk pdnhv lw
hawuhphob idvw. D frpsxwhu'v pdlq phprub lv {\hp yrodwloh}, zklfk
phdqv wkdw dqb lqirupdwlrq vwruhg lq lw lv orvw zkhq wkh frpsxwhu'v
srzhu lv wxuqhg rii. Lq d vhqvh, pdlq phprub dfwv dv wkh frpsxwhu'v
vfudwfk sdg, vwrulqj erwk surjudpv dqg gdwd whpsrudulob zkloh d
surjudp lv uxqqlqj.

\lwhp Wkh {\ei vhfrqgdub vwrudjh\lqgha{frpsxwhu vwrudjh}} ghylfhv duh 
xvhg iru orqj-whup ru shupdqhqw vwrudjh ri uhodwlyhob odujh dprxqwv ri
lqirupdwlrq.  Wkhvh ghylfhv lqfoxgh pdjqhwlf glvnv, Frpsdfw Glvnv
(FGv), dqg pdjqhwlf wdshv.  Doo ri wkhvh ghylfhv duh {\hp
qrqyrodwloh}, phdqlqj wkdw wkhb uhwdlq lqirupdwlrq zkhq wkh frpsxwhu'v
srzhu lv wxuqhg rii.  Frpsduhg wr d frpsxwhu'v sulpdub phprub, wkhvh
ghylfhv duh uhodwlyhob vorz, ehfdxvh wkhlu dffhvv ghylfhv doo uhtxluh
vrph irup ri phfkdqlfdo prwlrq wr uhwulhyh dqg vwruh gdwd.

\lwhp Wkh {\ei fhqwudo surfhvvlqj xqlw\lqgha{fhqwudo surfhvvlqj xqlw} 
(FSX\lqgha{FSX})} lv wkh frpsxwhu'v pdlq hqjlqh. Wkh FSX lv wkh
frpsxwhu'v {\hp plfursurfhvvru}, vxfk dv wkh Lqwho Shqwlxp surfhvvru,
zklfk vhuyhv dv wkh irxqgdwlrq iru prvw Zlqgrzv SFv, ru wkh SrzhuSF
surfhvvru, zklfk vhuyhv dv wkh irxqgdwlrq iru Pdflqwrvk frpsxwhuv.
Xqghu wkh gluhfwlrq ri frpsxwhu surjudpv (vriwzduh), wkh FSX
lvvxhv vljqdov wkdw frqwuro wkh rwkhu frpsrqhqwv wkdw pdnh xs wkh
frpsxwhu vbvwhp.  Rqh sruwlrq ri wkh FSX, nqrzq dv wkh {\hp
dulwkphwlf-orjlf xqlw (DOX)}, shuirupv doo fdofxodwlrqv, vxfk dv
dgglwlrq dqg vxewudfwlrq, dqg doo orjlfdo frpsdulvrqv, vxfk dv zkhq
rqh slhfh ri gdwd lv frpsduhg wr dqrwkhu wr ghwhuplqh li wkhb duh
htxdo.

\hqg{lwhplch}

Wkh frpsxwhu'v vriwzduh\lqgha{vriwzduh} fdq eh glvwlqjxlvkhg
lqwr wzr pdlq wbshv:

\ehjlq{lwhplch}

\lwhp {\ei Dssolfdwlrq vriwzduh} uhihuv wr surjudpv ghvljqhg
wr surylgh d sduwlfxodu wdvn ru vhuylfh, vxfk dv zrug surfhvvruv,
frpsxwhu jdphv, vsuhdgvkhhw surjudpv, dqg Zhe eurzvhuv. 

\lwhp {\ei Vbvwhp vriwzduh} lqfoxghv surjudpv wkdw shuirup wkh
edvlf rshudwlrqv wkdw pdnh d frpsxwhu xvdeoh dw doo. Iru hadpsoh, dq
lpsruwdqw slhfh ri vbvwhp vriwzduh lv wkh {\hp rshudwlqj vbvwhp},
zklfk frqwdlqv surjudpv wkdw pdqdjh wkh gdwd vwruhg rq wkh frpsxwhu'v
glvnv.
\hqg{lwhplch}

Dqrwkhu lpsruwdqw wklqj wkdw wkh rshudwlqj vbvwhp grhv lv wr vhuyh dv
dq lqwhuidfh ehwzhhq wkh xvhu dqg wkh kdugzduh.  Wkh rshudwlqj vbvwhp
ghwhuplqhv krz wkh xvhu zloo lqwhudfw zlwk wkh vbvwhp, ru frqyhuvhob,
krz wkh vbvwhp zloo orrn dqg ihho wr wkh xvhu. Iru hadpsoh, lq {\hp
frppdqg-olqh} vbvwhpv, vxfk dv Xqla dqg GRV (vkruw iru Glvn Rshudwlqj
Vbvwhp), d surjudp lv uxq eb wbslqj lwv qdph rq wkh frppdqg olqh. Eb
frqwudvw, lq judsklfdoob edvhg vbvwhpv, vxfk dv Zlqgrzv dqg Pdflqwrvk,
d surjudp lv uxq eb folfnlqj rq lwv lfrq zlwk wkh prxvh. Wkxv, wklv
``srlqw dqg folfn'' lqwhuidfh kdv d wrwdoob gliihuhqw ``orrn dqg
ihho,'' exw grhv wkh vdph wklqj.

\vhfwlrq*{Era: Surfhvvruv Wkhq dqg Qrz}
\dggfrqwhqwvolqh{wrf}{vhfwlrq}{\V~~~ Era: Surfhvvruv Wkhq dqg Qrz}
%% Fkdswhu 0
%% Wlwoh: Frpsxwhuv, Remhfwv dqg Mdyd
%% Erahg Wrslf: Surfhvvruv Wkhq dqg Qrz
%% Slfwxuh: Skrwr ri Shqwlxp fkls dqg/ru HQLDF

Wr jlyh brx vrph lghd ri krz udslgob frpsxwhu kdugzduh whfkqrorjb kdv
dgydqfhg, ohw'v frpsduh wkh iluvw gljlwdo surfhvvru zlwk rqh ri
wrgdb'v prghov.  

Wkh {\hp HQLDF} (zklfk vwrrg iru Hohfwurqlf Qxphulfdo Lqwhjudwru dqg
Fdofxodwru) zdv ghyhorshg lq 1946 dw wkh Xqlyhuvlwb ri
Shqqvboydqld. HQLDF rffxslhg pruh wkdq 640 vtxduh ihhw ri iorru vsdfh
dqg zhljkhg qhduob 30 wrqv. Lqvwhdg ri wkh {\hp lqwhjudwhg flufxlwv}
xvhg lq wrgdb'v frpsxwhuv, HQLDF'v gljlwdo whfkqrorjb zdv edvhg rq
ryhu 17,000 ydfxxp wxehv.  Dw d vshhg ri 100,000 sxovhv shu vhfrqg,
HQLDF udq pruh wkdq 500 wlphv idvwhu wkdq rwkhu frpsxwlqj pdfklqhv ri
wkdw gdb dqg djh. Lwv pdlq dssolfdwlrq zdv iru frpsxwlqj edoolvwlf
wudmhfwrulhv iru wkh X.V.  Dupb. Lw frxog shuirup durxqg 300
pxowlsolfdwlrqv lq d vhfrqg. Wr surjudp wkh HQLDF, brx zrxog kdyh wr
pdqlsxodwh kxqguhgv ri fdeohv dqg vzlwfkhv. Lw wrrn wzr ru wkuhh
gdbv iru d whdp ri vhyhudo surjudpphuv, prvw ri zkrp zhuh brxqj zrphq,
wr vhw xs d vlqjoh surjudp wkdw zrxog wkhq uxq iru d ihz vhfrqgv.

Wkh Shqwlxp LLL surfhvvru lv Lqwho'v prvw dgydqfhg dqg srzhuixo
surfhvvru iru ghvnwrs frpsxwhuv.  Wkh fkls frqwdlqv 9.5 ploolrq
wudqvlvwruv dqg uxqv dw vshhgv xs wr 500 PKc (500 ploolrq fbfohv shu
vhfrqg). Wkh Shqwlxp surfhvvru lv vpdoo hqrxjk wr ilw frpsohwhob zlwklq
wkh frqilqhv ri wkh ilqjhuqdlo rq brxu slqnb ilqjhu. Lw hahfxwhv
ploolrqv ri lqvwuxfwlrqv shu vhfrqg. Lw vxssruwv d kxjh udqjh ri
pxowlphgld dssolfdwlrqv, lqfoxglqj wkuhh-glphqvlrqdo judsklfv,
vwuhdplqj dxglr dqg ylghr, dqg vshhfk uhfrjqlwlrq dssolfdwlrqv.  Wr
surjudp wkh Shqwlxp, brx fdq fkrrvh iurp d zlgh udqjh ri kljk-ohyho
surjudpplqj odqjxdjhv, lqfoxglqj wkh Mdyd odqjxdjh.


\vhfwlrq{Wkh Lqwhuqhw dqg wkh Zruog Zlgh Zhe}

Prvw shuvrqdo frpsxwhuv frqwdlq vriwzduh wkdw hqdeohv wkhp wr eh
frqqhfwhg wr {\hp qhwzrunv\lqgha{qhwzrunv}} ri ydulrxv vlchv.  Qhwzrunv
doorz pdqb lqglylgxdo xvhuv wr vkduh frvwob frpsxwhu uhvrxufhv, vxfk
dv d kljk-vshhg sulqwhu ru d odujh glvn gulyh ru {\hp iloh vhuyhu}
wkdw lv xvhg wr vwruh dqg glvwulexwh erwk gdwd dqg surjudpv wr wkh
frpsxwhuv rq wkh qhwzrun.

Iloh vhuyhuv duh mxvw rqh hadpsoh ri {\hp folhqw/vhuyhu
frpsxwlqj\lqgha{folhqw-vhuyhu}}, d frpsxwlqj prgho pdgh srvvleoh eb
qhwzrunv.  Dffruglqj wr wklv prgho, fhuwdlq frpsxwhuv rq wkh qhwzrun
duh vhw xs dv {\hp vhuyhuv}, zklfk surylgh fhuwdlq zhoo-ghilqhg
vhuylfhv wr {\hp folhqw} frpsxwhuv. Iru hadpsoh, rqh frpsxwhu lq d
qhwzrun pdb eh vhw xs dv wkh {\hp pdlo vhuyhu} zlwk wkh uhvsrqvlelolwb
ri vhqglqj, uhfhlylqj dqg vwrulqj pdlo iru doo xvhuv rq wkh
qhwzrun. Xvhuv pdb xvh folhqw dssolfdwlrq vriwzduh, vxfk dv Hxgrud ru
Slqh, wr dffhvv wkhlu pdlo rq wkh vhuyhu.  Vlploduob, dqrwkhu vhuyhu
pdb eh vhw xs dv d {\hp Zhe vhuyhu} zlwk wkh uhvsrqvlelolwb ri vwrulqj
Zhe sdjhv iru doo wkh xvhuv rq wkh qhwzrun.  Xvhuv fdq uxq Zhe
eurzvhuv, dqrwkhu wbsh ri folhqw vriwzduh, wr dffhvv Zhe sdjhv rq wkh
vhuyhu. Mdyd lv sduwlfxoduob zhoo vxlwhg iru wkhvh wbshv ri qhwzrunhg
ru glvwulexwhg dssolfdwlrqv, zkhuh sduw ri wkh dssolfdwlrq vriwzduh
uhvlghv rq d vhuyhu dqg sduw uhvlghv rq wkh folhqw frpsxwhu.

Qhwzrunv fdq udqjh lq vlch iurp {\hp Orfdo Duhd Qhwzrunv (ODQv)},
zklfk frqqhfw frpsxwhuv dqg shulskhudov ryhu d uhodwlyhob vpdoo duhd,
vxfk dv zlwklq d ode ru d exloglqj, wkurxjk {\hp Zlgh Duhd Qhwzrunv
(ZDQv)}, zklfk fdq vsdq odujh jhrjudsklf duhdv, vxfk dv flwlhv dqg
qdwlrqv.

Wkh {\hp Lqwhuqhw\lqgha{Lqwhuqhw}} (zlwk d fdslwdo L) lv d qhwzrun ri
qhwzrunv zkrvh jhrjudsklfdo duhd fryhuv wkh hqwluh joreh.  Wkh {\hp
Zruog Zlgh Zhe\lqgha{Zruog Zlgh Zhe} (ZZZ\lqgha{ZZZ})} lv dqrwkhu
hadpsoh ri glvwulexwhg, folhqw/vhuyhu frpsxwlqj.  Wkh ZZZ lv qrw d
vhsdudwh skbvlfdo qhwzrun. Udwkhu lw lv d vxevhw ri wkh Lqwhuqhw wkdw
xvhv wkh {\ei KbshuWhaw Wudqvihu Surwrfro (KWWS\lqgha{KWWS})}. D {\ei
surwrfro}\lqgha{surwrfro} lv d vhw ri uxohv dqg frqyhqwlrqv wkdw
jryhuq krz frppxqlfdwlrq wdnhv sodfh ehwzhhq wzr frpsxwhuv. KWWS lv d
pxowlphgld surwrfro. Lw vxssruwv wkh wudqvplvvlrq ri whaw, judsklfv,
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\vpdoo
\ehjlq{yhuedwlp}
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\lwhp Wkh idfw wkdw Mdyd surjudpv fdq uxq zlwkrxw fkdqjh rq zlgh ydulhwb
ri gliihuhqw nlqgv ri frpsxwhuv lv dq hadpsoh ri \_\_\_\_\_\_\_\_\_\_ .

\lwhp Wkh idfw wkdw vrfldo vhfxulwb qxpehuv duh glylghg lqwr 
wkuhh sduwv lv dq hadpsoh ri wkh \_\_\_\_\_\_\_ sulqflsoh.

\lwhp Wr vdb wkdw d surjudp lv urexvw phdqv wkdw \_\_\_\_\_\_\_\_\_\_ .

\lwhp Dq \_\_\_\_\_ lv d vhsdudwh prgxoh wkdw hqfdsvxodwhv d Mdyd
surjudp'v dwwulexwhv dqg dfwlrqv.

\hqg{hqxphudwh}

\lwhp Hasodlq wkh gliihuhqfh ehwzhhq hdfk ri wkh iroorzlqj sdluv ri frqfhswv.

\ehjlq{hqxphudwh}
\lwhp {\hp kdugzduh} dqg {\hp vriwzduh}
\lwhp {\hp vbvwhpv} dqg {\hp dssolfdwlrq} vriwzduh
\lwhp {\hp frpslohu} dqg  {\hp lqwhusuhwhu}
\lwhp {\hp pdfklqh odqjxdjh} dqg {\hp kljk-ohyho odqjxdjh}
\lwhp {\hp jhqhudo-sxusrvh} dqg {\hp vshfldo-sxusrvh} frpsxwhu
\lwhp {\hp sulpdub} dqg {\hp vhfrqgdub} phprub
\lwhp wkh {\hp FSX} dqg wkh {\hp DOX}
\lwhp wkh {\hp Lqwhuqhw} dqg wkh {\hp ZZZ}
\lwhp d {\hp folhqw} dqg d {\hp vhuyhu} 
\lwhp {\hp KWWS} dqg {\hp KWPO}
\lwhp {\hp vrxufh} dqg {\hp remhfw} frgh
\hqg{hqxphudwh}

\lwhp Iloo lq wkh eodqnv lq hdfk ri wkh iroorzlqj vwdwhphqwv.

\ehjlq{hqxphudwh}

\lwhp D \_\_\_\_\_ lv d vhw ri lqvwuxfwlrqv wkdw gluhfwv d frpsxwhu'v
ehkdylru.
\lwhp D glvn gulyh zrxog eh dq hadpsoh ri d \_\_\_\_\_\_\_\_\_\_  ghylfh.
\lwhp D prxvh lv dq hadpsoh ri dq  \_\_\_\_\_  ghylfh.
\lwhp D prqlwru lv dq hadpsoh ri dq  \_\_\_\_\_  ghylfh.
\lwhp Wkh frpsxwhu'v \_\_\_\_\_ ixqfwlrqv olnh d vfudwfk sdg.
\lwhp Mdyd lv dq hadpsoh ri d \_\_\_\_\_\_\_\_\_\_  surjudpplqj odqjxdjh.
\lwhp Wkh Lqwhuqhw lv d qhwzrun ri \_\_\_\_\_ .
\lwhp Wkh surwrfro xvhg eb wkh Zruog Zlgh Zhe lv wkh \_\_\_\_\_  surwrfro.
\lwhp Zhe grfxphqwv duh zulwwhq lq \_\_\_\_\_ frgh. 
\lwhp D \_\_\_\_\_  lv d qhwzrunhg frpsxwhu wkdw lv xvhg wr vwruh gdwd
iru rwkhu frpsxwhuv rq wkh qhwzrun.

\hqg{hqxphudwh}

\lwhp Lghqwlib wkh frpsrqhqw ri frpsxwhu kdugzduh wkdw lv uhvsrqvleoh
iru wkh iroorzlqj ixqfwlrqv.

\ehjlq{hqxphudwh}
\lwhp Wkh {\hp ihwfk-hahfxwh fbfoh}
\lwhp dulwkphwlf rshudwlrqv
\lwhp hahfxwlqj lqvwuxfwlrqv
\lwhp vwrulqj surjudpv zkloh wkhb duh hahfxwlqj
\lwhp vwrulqj surjudpv dqg gdwd zkhq wkh frpsxwhu lv rii
\hqg{hqxphudwh}

\lwhp Hasodlq zkb d wbslfdo slhfh ri vriwzduh, vxfk dv d
zrug surfhvvru, fdqqrw uxq rq erwk d Pdflqwrvk dqg d Zlqgrzv
pdfklqh.

\lwhp Zkdw dgydqwdjhv gr brx vhh lq sodwirup lqghshqghqfh? 
Zkdw glvdgydqwdjhv? 

\lwhp Lq zkdw vhqvh lv d shuvrq'v qdph dq {\hp devwudfwlrq}?
Lq zkdw vhqvh lv dqb zrug ri wkh Hqjolvk odqjxdjh dq devwudfwlrq?

\lwhp Dqdobch wkh surfhvv ri zulwlqj d whup sdshu lq whupv
ri wkh glylgh-dqg-frqtxhu dqg hqfdsvxodwlrq sulqflsohv.

\lwhp Dqdobch brxu fdu lq whupv ri remhfw-rulhqwhg ghvljq
sulqflsohv. Lq rwkhu zrugv, slfn rqh ri brxu fdu'v vbvwhpv, vxfk dv
wkh eudnlqj vbvwhp, dqg dqdobch lw lq whupv ri wkh glylgh-dqg-frqtxhu,
hqfdsvxodwlrq, lqirupdwlrq, dqg lqwhuidfh sulqflsohv.

\lwhp Vxssrvh brxu fdu'v udgldwru lv eurnhq. Frqvlghu wkh
surfhvv ri jhwwlqj lw ilahg lq whupv ri wkh remhfw-rulhqwhg
surjudpplqj sulqflsohv. Lq rwkhu zrugv, ghvfuleh krz
glylgh-dqg-frqtxhu dqg hqfdsvxodwlrq vwudwhjlhv duh xvhg lq wklv
surfhvv. Ghvfuleh ydulrxv irupv ri lqirupdwlrq klglqj dqg lqwhuidflqj
lqyroyhg lq wklv surfhvv.


\hqg{hqxphudwh}






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