<s>
is	O
a	O
free	B-Application
and	O
open-source	B-Application
gravity	O
simulator	O
distributed	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
The	O
program	O
is	O
available	O
for	O
all	O
major	O
operating	B-General_Concept
systems	I-General_Concept
,	O
including	O
Linux	B-Application
and	O
other	O
Unix-like	B-Operating_System
systems	I-Operating_System
,	O
Microsoft	B-Application
Windows	I-Application
and	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
.	O
</s>
<s>
Gravit	B-Application
uses	O
the	O
Barnes	O
–	O
Hut	O
algorithm	O
to	O
simulate	O
the	O
n-body	O
problem	O
.	O
</s>
<s>
Gravit	B-Application
is	O
a	O
gravity	O
simulator	O
which	O
runs	O
under	O
Linux	B-Application
,	O
Windows	O
and	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
.	O
</s>
<s>
It	O
is	O
released	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
which	O
makes	O
it	O
free	B-Application
.	O
</s>
<s>
Although	O
the	O
main	O
goal	O
of	O
Gravit	B-Application
is	O
to	O
be	O
as	O
accurate	O
as	O
possible	O
,	O
it	O
also	O
creates	O
beautiful	O
looking	O
gravity	O
patterns	O
.	O
</s>
<s>
Gravit	B-Application
uses	O
OpenGL	O
with	O
Lua	B-Language
,	O
SDL	O
,	O
SDL_ttf	O
and	O
SDL_image	O
.	O
</s>
