<s>
The	O
Manchester	B-Device
computers	I-Device
were	O
an	O
innovative	O
series	O
of	O
stored-program	B-Architecture
electronic	O
computers	O
developed	O
during	O
the	O
30-year	O
period	O
between	O
1947	O
and	O
1977	O
by	O
a	O
small	O
team	O
at	O
the	O
University	O
of	O
Manchester	O
,	O
under	O
the	O
leadership	O
of	O
Tom	O
Kilburn	O
.	O
</s>
<s>
They	O
included	O
the	O
world	O
's	O
first	O
stored-program	B-Architecture
computer	O
,	O
the	O
world	O
's	O
first	O
transistorised	O
computer	O
,	O
and	O
what	O
was	O
the	O
world	O
's	O
fastest	O
computer	O
at	O
the	O
time	O
of	O
its	O
inauguration	O
in	O
1962	O
.	O
</s>
<s>
The	O
project	O
began	O
with	O
two	O
aims	O
:	O
to	O
prove	O
the	O
practicality	O
of	O
the	O
Williams	B-General_Concept
tube	I-General_Concept
,	O
an	O
early	O
form	O
of	O
computer	B-General_Concept
memory	I-General_Concept
based	O
on	O
standard	O
cathode-ray	B-Device
tubes	I-Device
(	O
CRTs	O
)	O
;	O
and	O
to	O
construct	O
a	O
machine	O
that	O
could	O
be	O
used	O
to	O
investigate	O
how	O
computers	O
might	O
be	O
able	O
to	O
assist	O
in	O
the	O
solution	O
of	O
mathematical	O
problems	O
.	O
</s>
<s>
The	O
first	O
of	O
the	O
series	O
,	O
the	O
Manchester	B-Device
Baby	I-Device
,	O
ran	O
its	O
first	O
program	O
on	O
21	O
June	O
1948	O
.	O
</s>
<s>
As	O
the	O
world	O
's	O
first	O
stored-program	B-Architecture
computer	O
,	O
the	O
Baby	O
,	O
and	O
the	O
Manchester	B-Device
Mark	I-Device
1	I-Device
developed	O
from	O
it	O
,	O
quickly	O
attracted	O
the	O
attention	O
of	O
the	O
United	O
Kingdom	O
government	O
,	O
who	O
contracted	O
the	O
electrical	O
engineering	O
firm	O
of	O
Ferranti	O
to	O
produce	O
a	O
commercial	O
version	O
.	O
</s>
<s>
The	O
resulting	O
machine	O
,	O
the	O
Ferranti	B-Device
Mark	I-Device
1	I-Device
,	O
was	O
the	O
world	O
's	O
first	O
commercially	O
available	O
general-purpose	O
computer	O
.	O
</s>
<s>
The	O
collaboration	O
with	O
Ferranti	O
eventually	O
led	O
to	O
an	O
industrial	O
partnership	O
with	O
the	O
computer	O
company	O
ICL	O
,	O
who	O
made	O
use	O
of	O
many	O
of	O
the	O
ideas	O
developed	O
at	O
the	O
university	O
,	O
particularly	O
in	O
the	O
design	O
of	O
their	O
2900	B-Device
series	I-Device
of	O
computers	O
during	O
the	O
1970s	O
.	O
</s>
<s>
The	O
Manchester	B-Device
Baby	I-Device
was	O
designed	O
as	O
a	O
test-bed	O
for	O
the	O
Williams	B-General_Concept
tube	I-General_Concept
,	O
an	O
early	O
form	O
of	O
computer	B-General_Concept
memory	I-General_Concept
,	O
rather	O
than	O
as	O
a	O
practical	O
computer	O
.	O
</s>
<s>
Its	O
successful	O
operation	O
was	O
reported	O
in	O
a	O
letter	O
to	O
the	O
journal	O
Nature	O
published	O
in	O
September	O
1948	O
,	O
establishing	O
it	O
as	O
the	O
world	O
's	O
first	O
stored-program	B-Architecture
computer	O
.	O
</s>
<s>
It	O
quickly	O
evolved	O
into	O
a	O
more	O
practical	O
machine	O
,	O
the	O
Manchester	B-Device
Mark	I-Device
1	I-Device
.	O
</s>
<s>
Development	O
of	O
the	O
Manchester	B-Device
Mark	I-Device
1	I-Device
began	O
in	O
August	O
1948	O
,	O
with	O
the	O
initial	O
aim	O
of	O
providing	O
the	O
university	O
with	O
a	O
more	O
realistic	O
computing	O
facility	O
.	O
</s>
<s>
In	O
October	O
1948	O
UK	O
Government	O
Chief	O
Scientist	O
Ben	O
Lockspeiser	O
was	O
given	O
a	O
demonstration	O
of	O
the	O
prototype	O
,	O
and	O
was	O
so	O
impressed	O
that	O
he	O
immediately	O
initiated	O
a	O
government	O
contract	O
with	O
the	O
local	O
firm	O
of	O
Ferranti	O
to	O
make	O
a	O
commercial	O
version	O
of	O
the	O
machine	O
,	O
the	O
Ferranti	B-Device
Mark	I-Device
1	I-Device
.	O
</s>
<s>
Two	O
versions	O
of	O
the	O
Manchester	B-Device
Mark	I-Device
1	I-Device
were	O
produced	O
,	O
the	O
first	O
of	O
which	O
,	O
the	O
Intermediary	O
Version	O
,	O
was	O
operational	O
by	O
April	O
1949	O
.	O
</s>
<s>
Perhaps	O
the	O
Manchester	B-Device
Mark	I-Device
1	I-Device
's	O
most	O
significant	O
innovation	O
was	O
its	O
incorporation	O
of	O
index	B-General_Concept
registers	I-General_Concept
,	O
commonplace	O
on	O
modern	O
computers	O
.	O
</s>
<s>
They	O
therefore	O
embarked	O
on	O
the	O
design	O
of	O
a	O
new	O
machine	O
which	O
would	O
include	O
a	O
floating-point	B-General_Concept
unit	I-General_Concept
;	O
work	O
began	O
in	O
1951	O
.	O
</s>
<s>
Ferranti	O
produced	O
a	O
commercial	O
version	O
marketed	O
as	O
the	B-Device
Ferranti	I-Device
Mercury	I-Device
,	O
in	O
which	O
the	O
Williams	B-General_Concept
tubes	I-General_Concept
were	O
replaced	O
by	O
the	O
more	O
reliable	O
core	B-General_Concept
memory	I-General_Concept
.	O
</s>
<s>
Two	O
of	O
Kilburn	O
's	O
team	O
,	O
Richard	O
Grimsdale	O
and	O
D	O
.	O
C	O
.	O
Webb	O
,	O
were	O
assigned	O
to	O
the	O
task	O
of	O
designing	O
and	O
building	O
a	O
machine	O
using	O
the	O
newly	O
developed	O
transistors	B-Application
instead	O
of	O
valves	O
,	O
which	O
became	O
known	O
as	O
the	O
Manchester	O
TC	O
.	O
</s>
<s>
Initially	O
the	O
only	O
devices	O
available	O
were	O
germanium	O
point-contact	O
transistors	B-Application
,	O
less	O
reliable	O
than	O
the	O
valves	O
they	O
replaced	O
but	O
which	O
consumed	O
far	O
less	O
power	O
.	O
</s>
<s>
"	O
The	O
48-bit	O
machine	O
used	O
92	O
point-contact	O
transistors	B-Application
and	O
550	O
diodes	O
"	O
.	O
</s>
<s>
The	O
1955	O
version	O
used	O
250	O
junction	O
transistors	B-Application
,	O
1,300	O
solid-state	O
diodes	O
,	O
and	O
had	O
a	O
power	O
consumption	O
of	O
150	O
watts	O
.	O
</s>
<s>
The	O
machine	O
did	O
however	O
make	O
use	O
of	O
valves	O
to	O
generate	O
its	O
125kHz	O
clock	O
waveforms	O
and	O
in	O
the	O
circuitry	O
to	O
read	O
and	O
write	O
on	O
its	O
magnetic	B-General_Concept
drum	I-General_Concept
memory	I-General_Concept
,	O
so	O
it	O
was	O
not	O
the	O
first	O
completely	O
transistorised	O
computer	O
,	O
a	O
distinction	O
that	O
went	O
to	O
the	O
Harwell	B-Device
CADET	I-Device
of	O
1955	O
.	O
</s>
<s>
Problems	O
with	O
the	O
reliability	O
of	O
early	O
batches	O
of	O
transistors	B-Application
meant	O
that	O
the	O
machine	O
's	O
mean	O
time	O
between	O
failures	O
was	O
about	O
90	O
minutes	O
,	O
which	O
improved	O
once	O
the	O
more	O
reliable	O
junction	O
transistors	B-Application
became	O
available	O
.	O
</s>
<s>
The	O
Transistor	B-Application
Computer	O
's	O
design	O
was	O
adopted	O
by	O
the	O
local	O
engineering	O
firm	O
of	O
Metropolitan-Vickers	O
in	O
their	O
Metrovick	B-Device
950	I-Device
,	O
in	O
which	O
all	O
the	O
circuitry	O
was	O
modified	O
to	O
make	O
use	O
of	O
junction	O
transistors	B-Application
.	O
</s>
<s>
Six	O
Metrovick	B-Device
950s	I-Device
were	O
built	O
,	O
the	O
first	O
completed	O
in	O
1956	O
.	O
</s>
<s>
At	O
the	O
end	O
of	O
1958	O
Ferranti	O
agreed	O
to	O
collaborate	O
with	O
Manchester	O
University	O
on	O
the	O
project	O
,	O
and	O
the	O
computer	O
was	O
shortly	O
afterwards	O
renamed	O
Atlas	B-Device
,	O
with	O
the	O
joint	O
venture	O
under	O
the	O
control	O
of	O
Tom	O
Kilburn	O
.	O
</s>
<s>
The	O
first	O
Atlas	B-Device
was	O
officially	O
commissioned	O
on	O
7	O
December	O
1962	O
,	O
and	O
was	O
considered	O
at	O
that	O
time	O
to	O
be	O
the	O
most	O
powerful	O
computer	O
in	O
the	O
world	O
,	O
equivalent	O
to	O
four	O
IBM	B-Device
7094s	I-Device
.	O
</s>
<s>
It	O
was	O
said	O
that	O
whenever	O
Atlas	B-Device
went	O
offline	O
half	O
of	O
the	O
UK	O
's	O
computer	O
capacity	O
was	O
lost	O
.	O
</s>
<s>
Its	O
fastest	O
instructions	O
took	O
1.59	O
microseconds	O
to	O
execute	O
,	O
and	O
the	O
machine	O
's	O
use	O
of	O
virtual	B-Architecture
storage	I-Architecture
and	O
paging	O
allowed	O
each	O
concurrent	O
user	O
to	O
have	O
up	O
to	O
one	O
million	O
words	O
of	O
storage	O
space	O
available	O
.	O
</s>
<s>
Atlas	B-Device
pioneered	O
many	O
hardware	O
and	O
software	O
concepts	O
still	O
in	O
common	O
use	O
today	O
including	O
the	O
Atlas	B-Application
Supervisor	I-Application
,	O
"	O
considered	O
by	O
many	O
to	O
be	O
the	O
first	O
recognisable	O
modern	O
operating	B-General_Concept
system	I-General_Concept
"	O
.	O
</s>
<s>
Two	O
other	O
machines	O
were	O
built	O
:	O
one	O
for	O
a	O
joint	O
British	O
Petroleum/University	O
of	O
London	O
consortium	O
,	O
and	O
the	O
other	O
for	O
the	O
Atlas	B-Device
Computer	I-Device
Laboratory	O
at	O
Chilton	O
near	O
Oxford	O
.	O
</s>
<s>
A	O
derivative	O
system	O
was	O
built	O
by	O
Ferranti	O
for	O
Cambridge	O
University	O
,	O
called	O
the	O
Titan	B-Device
or	O
Atlas	B-Device
2	O
,	O
which	O
had	O
a	O
different	O
memory	O
organisation	O
,	O
and	O
ran	O
a	O
time-sharing	B-General_Concept
operating	I-General_Concept
system	I-General_Concept
developed	O
by	O
Cambridge	O
Computer	O
Laboratory	O
.	O
</s>
<s>
The	O
University	O
of	O
Manchester	O
's	O
Atlas	B-Device
was	O
decommissioned	O
in	O
1971	O
,	O
but	O
the	O
last	O
was	O
in	O
service	O
until	O
1974	O
.	O
</s>
<s>
Parts	O
of	O
the	O
Chilton	B-Device
Atlas	I-Device
are	O
preserved	O
by	O
the	O
National	O
Museums	O
of	O
Scotland	O
in	O
Edinburgh	O
.	O
</s>
<s>
The	O
Manchester	O
MU5	O
was	O
the	O
successor	O
to	O
Atlas	B-Device
.	O
</s>
<s>
An	O
outline	O
proposal	O
for	O
a	O
successor	O
to	O
Atlas	B-Device
was	O
presented	O
at	O
the	O
1968	O
IFIP	O
Conference	O
in	O
Edinburgh	O
,	O
although	O
work	O
on	O
the	O
project	O
and	O
talks	O
with	O
ICT	O
(	O
of	O
which	O
Ferranti	O
had	O
become	O
part	O
)	O
aimed	O
at	O
obtaining	O
their	O
assistance	O
and	O
support	O
had	O
begun	O
in	O
1966	O
.	O
</s>
<s>
The	O
new	O
machine	O
,	O
later	O
to	O
become	O
known	O
as	O
MU5	O
,	O
was	O
intended	O
to	O
be	O
at	O
the	O
top	O
end	O
of	O
a	O
range	O
of	O
machines	O
and	O
to	O
be	O
20	O
times	O
faster	O
than	O
Atlas	B-Device
.	O
</s>
<s>
The	O
most	O
significant	O
novel	O
features	O
of	O
the	O
MU5	O
processor	O
were	O
its	O
instruction	O
set	O
and	O
the	O
use	O
of	O
associative	B-Data_Structure
memory	I-Data_Structure
to	O
speed	O
up	O
operand	O
and	O
instruction	O
accesses	O
.	O
</s>
<s>
The	O
MU5	O
operating	B-General_Concept
system	I-General_Concept
MUSS	O
was	O
designed	O
to	O
be	O
highly	O
adaptable	O
and	O
was	O
ported	O
to	O
a	O
variety	O
of	O
processors	O
at	O
Manchester	O
and	O
elsewhere	O
.	O
</s>
<s>
In	O
the	O
completed	O
MU5	O
system	O
,	O
three	O
processors	O
(	O
MU5	O
itself	O
,	O
an	O
ICL	B-Device
1905E	I-Device
and	O
a	O
PDP-11	B-Device
)	O
,	O
as	O
well	O
as	O
a	O
number	O
of	O
memories	O
and	O
other	O
devices	O
,	O
were	O
interconnected	O
by	O
a	O
high-speed	O
Exchange	O
.	O
</s>
<s>
MU5	O
was	O
fully	O
operational	O
by	O
October	O
1974	O
,	O
coinciding	O
with	O
ICL	O
's	O
announcement	O
that	O
it	O
was	O
working	O
on	O
the	O
development	O
of	O
a	O
new	O
range	O
of	O
computers	O
,	O
the	O
2900	B-Device
series	I-Device
.	O
</s>
<s>
A	O
prototype	O
model	O
of	O
MU6V	O
,	O
based	O
on	O
68000	O
microprocessors	O
with	O
vector	O
orders	O
emulated	O
as	O
"	O
extracodes	B-Device
"	O
was	O
constructed	O
and	O
tested	O
but	O
not	O
further	O
developed	O
beyond	O
this	O
.	O
</s>
<s>
MU6-G	O
was	O
built	O
with	O
a	O
grant	O
from	O
SRC	O
and	O
successfully	O
ran	O
as	O
a	O
service	O
machine	O
in	O
the	O
Department	O
between	O
1982	O
and	O
1987	O
,	O
using	O
the	O
MUSS	O
operating	B-General_Concept
system	I-General_Concept
developed	O
as	O
part	O
of	O
the	O
MU5	O
project	O
.	O
</s>
<s>
SpiNNaker	O
:	O
Spiking	B-Algorithm
Neural	I-Algorithm
Network	I-Algorithm
Architecture	O
is	O
a	O
massively	B-Operating_System
parallel	I-Operating_System
,	O
manycore	B-General_Concept
supercomputer	B-Operating_System
architecture	I-Operating_System
designed	O
by	O
Steve	O
Furber	O
in	O
the	O
University	O
of	O
Manchester	O
's	O
Advanced	O
Processor	O
Technologies	O
Research	O
Group	O
(	O
APT	O
)	O
.	O
</s>
<s>
The	O
computing	O
platform	O
is	O
based	O
on	O
spiking	B-Algorithm
neural	I-Algorithm
networks	I-Algorithm
,	O
useful	O
in	O
simulating	O
the	O
human	O
brain	O
(	O
see	O
Human	O
Brain	O
Project	O
)	O
.	O
</s>
<s>
+	O
Chronology	O
of	O
developments	O
Year	O
University	O
Prototype	O
Year	O
Commercial	O
Computer	O
1948	O
Manchester	B-Device
Baby	I-Device
,	O
which	O
evolved	O
into	O
the	O
Manchester	B-Device
Mark	I-Device
1	I-Device
1951	O
Ferranti	B-Device
Mark	I-Device
1	I-Device
1953	O
Transistor	B-Application
computer	O
1956	O
Metrovick	B-Device
950	I-Device
1954	O
Manchester	O
Mark	O
II	O
a.k.a.	O
</s>
