<s>
Cactus	B-Language
is	O
an	O
open-source	B-Application
,	O
problem-solving	O
environment	B-Architecture
designed	O
for	O
scientists	O
and	O
engineers	O
.	O
</s>
<s>
Its	O
modular	B-Architecture
structure	O
enables	O
parallel	B-Operating_System
computation	I-Operating_System
across	O
different	O
architectures	O
and	O
collaborative	O
code	O
development	O
between	O
different	O
groups	O
.	O
</s>
<s>
Cactus	B-Language
originated	O
in	O
the	O
academic	O
research	O
community	O
,	O
where	O
it	O
was	O
developed	O
and	O
used	O
over	O
many	O
years	O
by	O
a	O
large	O
international	O
collaboration	O
of	O
physicists	O
and	O
computational	B-Application
scientists	I-Application
.	O
</s>
<s>
The	O
name	O
Cactus	B-Language
comes	O
from	O
the	O
design	B-General_Concept
of	O
a	O
central	O
core	O
(	O
or	O
"	O
flesh	O
"	O
)	O
which	O
connects	O
to	O
application	O
modules	B-Architecture
(	O
or	O
"	O
thorns	O
"	O
)	O
through	O
an	O
extensible	O
interface	O
.	O
</s>
<s>
Cactus	B-Language
runs	O
on	O
many	O
architectures	O
.	O
</s>
<s>
Applications	O
,	O
developed	O
on	O
standard	O
workstations	B-Device
or	O
laptops	B-Device
,	O
can	O
be	O
seamlessly	O
run	O
on	O
clusters	O
or	O
supercomputers	B-Architecture
.	O
</s>
<s>
Cactus	B-Language
provides	O
easy	O
access	O
to	O
many	O
cutting-edge	O
software	O
technologies	O
being	O
developed	O
in	O
the	O
academic	O
research	O
community	O
,	O
including	O
the	O
Globus	O
Toolkit	O
,	O
HDF5	B-Application
parallel	O
file	O
I/O	O
,	O
the	O
PETSc	B-Language
scientific	O
library	O
,	O
adaptive	B-Algorithm
mesh	I-Algorithm
refinement	I-Algorithm
,	O
web	O
interfaces	O
,	O
and	O
advanced	O
visualization	B-Application
tools	O
.	O
</s>
<s>
Cactus	B-Language
was	O
originally	O
developed	O
at	O
the	O
AEI	O
,	O
and	O
is	O
now	O
developed	O
jointly	O
at	O
AEI	O
,	O
Cardiff	O
University	O
,	O
and	O
the	O
Center	O
for	O
Computation	O
&	O
Technology	O
at	O
LSU	O
.	O
</s>
<s>
There	O
are	O
several	O
large	O
packages	O
built	O
on	O
Cactus	B-Language
,	O
among	O
others	O
a	O
general	O
relativistic	O
spacetime	B-Protocol
evolution	O
code	O
,	O
an	O
adaptive	B-Algorithm
mesh	I-Algorithm
refinement	I-Algorithm
driver	O
(	O
Carpet	O
)	O
,	O
and	O
a	O
general	O
relativistic	O
hydrodynamics	O
code	O
(	O
Whisky	O
)	O
.	O
</s>
<s>
Staff	O
with	O
the	O
LSU	O
Center	O
for	O
Computation	O
&	O
Technology	O
,	O
who	O
were	O
part	O
of	O
the	O
original	O
group	O
at	O
AEI	O
who	O
created	O
Cactus	B-Language
,	O
celebrated	O
the	O
program	O
's	O
10th	O
birthday	O
in	O
April	O
2007	O
.	O
</s>
