,MANCHESTER ,MARK #A
,THE ,MANCHESTER ,MARK #A WAS THE
COMPUTER THE ,BABY GREW INTO  AND THE
PROTOTYPE EVERY COMMERCIAL COMPUTER
DESCENDS FROM4 ,FREDERIC ,WILLIAMS1 ,TOM
,KILBURN1 AND ,GEOFF ,TOOTILL BUILT IT
AT ,VICTORIA ,UNIVERSITY OF ,MANCHESTER
FROM ,AUGUST #AIDH1 SCALING THEIR
,JUNE-#AIDH ,BABY INTO A REAL MACHINE3
INDEX REGISTERS "<THE FAMOUS
8;,B-LINES0">1 A MAGNETIC DRUM BACKING
STORE1 AND AN INSTRUCTION SET A HUMAN
COULD WORK WITH4 ,THE FIRST VERSION RAN
BY ,APRIL #AIDI2 ON THE NIGHT OF
#AF_/#AG ,JUNE #AIDI A ,MERSENNE-PRIME
SEARCH RAN NINE HOURS WITHOUT ERROR  THE
FIRST LONG COMPUTATION IN
HISTORY4.<CITE3 .<,MANCHESTER ,MARK #A 
THE DEVELOPMENT TEAM1 THE ,APRIL #AIDI
FIRST RUN1 AND THE NINE-HOUR ,MERSENNE
COMPUTATION.>.>
,THE ;,B-LINES DESERVE THEIR OWN
SENTENCE3 THE ,MARK #A WAS THE FIRST
COMPUTER WITH INDEX REGISTERS1 LETTING A
PROGRAM MODIFY ITS OWN ADDRESSES TO WALK
THROUGH AN ARRAY  THE ANCESTOR OF EVERY
ARRAY LOOP EVER WRITTEN4 ,THIRTY-FOUR
PATENTS CAME OUT OF THE PROJECT1 AND ITS
IDEAS SURFACED IN THE ,,IBM #GJA AND
#GJB AS WELL AS ITS OWN COMMERCIAL
DESCENDANT4.<CITE3 .<,MANCHESTER ,MARK
#A  INDEX REGISTERS1 THE #CD PATENTS1
AND THE ,,IBM #GJA_/#GJB INFLUENCE.>.>
8,ELECTRONIC BRAIN0  AND THE BIRTH OF
THE DEBATE
,THE ,BRITISH PRESS COVERED THE ,MARK #A
AS AN 8ELECTRONIC BRAIN0  AND THE PHRASE
PROVOKED THE FIRST RECORDED BACKLASH IN
,,AI'S LONG HISTORY3 THE HEAD OF
,MANCHESTER'S NEUROSURGERY DEPARTMENT
OBJECTED PUBLICLY1 OPENING A DEBATE
ABOUT WHETHER A COMPUTER COULD EVER BE
TRULY CREATIVE THAT HAS NOT YET ENDED4
,THE GOVERNMENT WAS QUICKER TO ACT3
,CHIEF ,SCIENTIST ,BEN ,LOCKSPEISER SAW
THE MACHINE IN ,OCTOBER #AIDH AND
IMMEDIATELY CONTRACTED ,FERRANTI TO
BUILD A COMMERCIAL VERSION  THE LETTER
AUTHORIZED THEM 8TO CONSTRUCT AN
ELECTRONIC CALCULATING MACHINE TO THE
INSTRUCTIONS OF ,PROFESSOR ;,F4 ;,C4
,WILLIAMS40.<CITE3 .<,MANCHESTER ,MARK
#A  THE 8ELECTRONIC BRAIN0 PRESS1 THE
NEUROSURGERY OBJECTION1 AND THE ,OCTOBER
#AIDH ,LOCKSPEISER,FERRANTI CONTRACT.>.>
,WHERE THE SOFTWARE ERA STARTED
,THE ,MARK #A'S SOFTWARE HISTORY MAY
OUTSHINE ITS HARDWARE4 ,ALAN ,TURING
JOINED ,MANCHESTER IN #AIDH AND WROTE
THE MACHINE'S INPUT ROUTINES AND MUCH OF
ITS PROGRAMMING MANUAL  THE
,PROGRAMMERS' ,HANDBOOK IS LARGELY HIS4
,AND ON THIS MACHINE'S LEGENDARILY
ABSTRUSE MACHINE CODE  TELEPRINTER-CODED
INSTRUCTIONS WITH THE BITS BACKWARDS 
,ALICK ,GLENNIE BUILT THE FIRST WORKING
,AUTOCODE IN #AIEB1 ARGUABLY THE FIRST
COMPILED LANGUAGE EVER RUN4 ,THE FIRST
MODERN MACHINE ALSO HOSTED THE FIRST
ATTEMPT TO MAKE PROGRAMMING LESS
MISERABLE4.<CITE3 .<,MANCHESTER ,MARK #A
PROGRAMMING AND THE ,AUTOCODE ARTICLE 
,TURING'S INPUT ROUTINES_/MANUAL AND
,GLENNIE'S #AIEB ,AUTOCODE.>.>
,THE ,MARK #A WAS SCRAPPED AT THE END OF
#AIEJ  BARELY EIGHTEEN MONTHS OLD 
BECAUSE ITS COMMERCIAL CLONE WAS READY4
,THE "9"9,FERRANTI ,MARK #A"9"91
DELIVERED ,FEBRUARY #AIEA1 WAS THE
WORLD'S FIRST COMMERCIALLY AVAILABLE
GENERAL-PURPOSE ELECTRONIC COMPUTER1
BEATING ,,UNIVAC'S FIRST DELIVERY BY
MONTHS4
,WHERE IT SITS
,THE ,MARK #A LIVED ONE AND A HALF YEARS
AND ITS OFFSPRING ARE STILL SHIPPING4
,BETWEEN THE ,BABY'S PROOF-OF-CONCEPT
AND THE ,FERRANTI'S PRODUCT LINE1 IT IS
THE HINGE MACHINE OF THE STORED-PROGRAM
ERA  THE FIRST COMPUTER WITH INDEX
REGISTERS1 ,TURING'S PROFESSIONAL HOME1
AND THE MACHINE WHOSE USERS IMMEDIATELY
INVENTED HIGH-LEVEL PROGRAMMING TO
ESCAPE IT4
,CHECK YOUR UNDERSTANDING
- .< .> ,WHAT MEMORY TECHNOLOGY DID THE
,MARK #A INHERIT FROM THE ,BABY8 - .< .>
,WHAT ARCHITECTURAL FEATURE  A FIRST 
DID THE ,MARK #A INTRODUCE FOR ARRAY
HANDLING8 - .< .> ,WHAT DID ,TURING
CONTRIBUTE TO THE ,MARK #A8 - .< .>
,WHAT DID THE ,MARK #A BECOME
COMMERCIALLY1 AND WHY IS THAT MACHINE
FIRST-OF-KIND8
#A  "9"9,WILLIAMS TUBES"9"9  ,,CRT-BASED
MEMORY "<THE ,BABY'S INVENTION">1 PLUS A
MAGNETIC DRUM4 #B  "9"9INDEX
REGISTERS"9"9 "<8;,B-LINES0">  PROGRAMS
COULD MODIFY ADDRESSES TO ITERATE
ARRAYS4 #C  THE "9"9INPUT ROUTINES AND
MUCH OF THE ,PROGRAMMERS' ,HANDBOOK"9"94
#D  THE "9"9,FERRANTI ,MARK #A"9"9
"<,FEB #AIEA">  THE WORLD'S FIRST
"9"9COMMERCIALLY AVAILABLE"9"9
GENERAL-PURPOSE ELECTRONIC COMPUTER4