<s>
OpenGrok	B-Protocol
is	O
a	O
source	O
code	O
search	O
and	O
cross-reference	O
engine	O
.	O
</s>
<s>
It	O
helps	O
programmers	O
to	O
search	O
,	O
cross-reference	O
,	O
and	O
navigate	O
source	O
code	O
trees	O
to	O
aid	O
code	B-General_Concept
comprehension	I-General_Concept
.	O
</s>
<s>
It	O
can	O
understand	O
various	O
program	B-Application
file	I-Application
formats	O
and	O
version	B-Architecture
control	I-Architecture
histories	O
like	O
Monotone	B-Application
,	O
SCCS	B-Device
,	O
RCS	B-Architecture
,	O
CVS	B-Application
,	O
Subversion	B-Application
,	O
Mercurial	B-Protocol
,	O
Git	B-Application
,	O
Clearcase	B-Protocol
,	O
Perforce	B-General_Concept
,	O
and	O
Bazaar	B-Protocol
.	O
</s>
<s>
The	O
name	O
comes	O
from	O
the	O
term	O
grok	B-Language
,	O
a	O
jargon	O
term	O
used	O
in	O
computing	O
to	O
mean	O
"	O
profoundly	O
understand.	O
"	O
</s>
<s>
OpenGrok	B-Protocol
is	O
being	O
developed	O
mainly	O
by	O
the	O
community	O
with	O
the	O
help	O
of	O
a	O
few	O
engineers	O
from	O
Oracle	B-Application
Corporation	I-Application
(	O
which	O
absorbed	O
Sun	O
Microsystems	O
)	O
.	O
</s>
<s>
OpenGrok	B-Protocol
is	O
released	O
under	O
the	O
terms	O
of	O
the	O
Common	B-Application
Development	I-Application
and	I-Application
Distribution	I-Application
License	I-Application
(	O
CDDL	B-Application
)	O
.	O
</s>
<s>
It	O
is	O
mainly	O
written	O
in	O
Java	B-Language
,	O
with	O
some	O
tooling	O
done	O
in	O
Python	B-Language
.	O
</s>
<s>
It	O
relies	O
on	O
the	O
analysis	O
done	O
by	O
Ctags	B-Device
.	O
</s>
<s>
OpenGrok	B-Protocol
supports	O
:	O
</s>
