<s>
is	O
free	B-Application
and	I-Application
open	I-Application
source	I-Application
general-purpose	O
diagramming	O
software	O
,	O
developed	O
originally	O
by	O
Alexander	O
Larsson	O
.	O
</s>
<s>
It	O
uses	O
a	O
controlled	O
single	O
document	O
interface	O
(	O
SDI	O
)	O
similar	O
to	O
GIMP	B-Application
and	O
Inkscape	B-Application
.	O
</s>
<s>
Dia	B-Operating_System
has	O
a	O
modular	O
design	O
with	O
several	O
shape	O
packages	O
available	O
for	O
different	O
needs	O
:	O
flowchart	B-Language
,	O
network	O
diagrams	O
,	O
circuit	B-Application
diagrams	I-Application
,	O
and	O
more	O
.	O
</s>
<s>
Dia	B-Operating_System
has	O
special	O
objects	O
to	O
help	O
draw	O
entity-relationship	B-Architecture
models	I-Architecture
,	O
Unified	B-Language
Modeling	I-Language
Language	I-Language
(	O
UML	B-Language
)	O
diagrams	O
,	O
flowcharts	B-Language
,	O
network	O
diagrams	O
,	O
and	O
simple	O
electrical	O
circuits	O
.	O
</s>
<s>
It	O
is	O
also	O
possible	O
to	O
add	O
support	O
for	O
new	O
shapes	O
by	O
writing	O
simple	O
XML	B-Protocol
files	O
,	O
using	O
a	O
subset	O
of	O
Scalable	B-Application
Vector	I-Application
Graphics	I-Application
(	O
SVG	B-Application
)	O
to	O
draw	O
the	O
shape	O
.	O
</s>
<s>
Dia	B-Operating_System
loads	O
and	O
saves	O
diagrams	O
in	O
a	O
custom	O
XML	B-Protocol
format	O
which	O
is	O
,	O
by	O
default	O
,	O
gzipped	O
to	O
save	O
space	O
.	O
</s>
<s>
It	O
can	O
print	O
large	O
diagrams	O
spanning	O
multiple	O
pages	O
and	O
can	O
also	O
be	O
scripted	O
using	O
the	O
Python	B-Language
programming	I-Language
language	I-Language
.	O
</s>
<s>
Dia	B-Operating_System
can	O
export	O
diagrams	O
to	O
various	O
formats	O
,	O
including	O
:	O
</s>
<s>
Dia	B-Operating_System
was	O
originally	O
created	O
by	O
Alexander	O
Larsson	O
,	O
but	O
he	O
moved	O
on	O
to	O
work	O
on	O
GNOME	B-Application
and	O
other	O
projects	O
.	O
</s>
<s>
Dia	B-Operating_System
is	O
currently	O
maintained	O
by	O
Hans	O
Breuer	O
,	O
Steffen	O
Macke	O
and	O
Sameer	O
Sahasrabuddhe	O
.	O
</s>
<s>
It	O
is	O
written	O
in	O
C	B-Language
,	O
and	O
has	O
an	O
extension	O
system	O
which	O
also	O
supports	O
writing	O
extensions	O
in	O
Python	B-Language
.	O
</s>
