<s>
JavaScript	B-Application
OSA	I-Application
,	O
(	O
originally	O
JavaScript	B-Language
for	O
OSA	O
,	O
abbreviated	O
as	O
JSOSA	O
)	O
,	O
is	O
a	O
freeware	B-License
inter-process	B-Operating_System
communication	I-Operating_System
scripting	B-Language
language	I-Language
for	O
the	O
Macintosh	B-Device
computer	I-Device
.	O
</s>
<s>
JavaScript	B-Application
OSA	I-Application
uses	O
the	O
"	O
core	O
language	O
"	O
of	O
the	O
Mozilla	B-Operating_System
implementation	O
of	O
the	O
JavaScript	B-Language
programming	I-Language
language	I-Language
,	O
(	O
see	O
SpiderMonkey	B-Language
)	O
.	O
</s>
<s>
The	O
language	O
is	O
used	O
as	O
an	O
alternative	O
to	O
the	O
AppleScript	B-Application
language	O
.	O
</s>
<s>
It	O
can	O
be	O
seen	O
as	O
having	O
a	O
similar	O
function	O
to	O
Microsoft	O
's	O
JScript	B-Language
.NET	I-Language
language	O
on	O
Windows	O
machines	O
,	O
although	O
there	O
is	O
no	O
interoperability	O
between	O
the	O
two	O
languages	O
 '	O
system-level	O
scripting	O
.	O
</s>
<s>
The	O
language	O
is	O
identical	O
to	O
Mozilla	B-Operating_System
's	O
core	O
language	O
,	O
with	O
extensions	O
added	O
via	O
a	O
"	O
Core	O
"	O
object	O
and	O
a	O
"	O
MacOS	O
"	O
object	O
.	O
</s>
<s>
The	O
MacOS	O
object	O
has	O
methods	O
for	O
obtaining	O
objects	O
that	O
are	O
bound	O
to	O
applications	B-Application
.	O
</s>
<s>
This	O
is	O
done	O
via	O
the	O
AppleEvent	B-Operating_System
messaging	B-Operating_System
system	I-Operating_System
,	O
a	O
part	O
of	O
the	O
Macintosh	B-Device
's	O
Open	O
Scripting	O
Architecture	O
.	O
</s>
<s>
The	O
language	O
was	O
first	O
released	O
in	O
2001	O
,	O
and	O
was	O
bundled	O
with	O
Late	O
Night	O
Software	O
's	O
flagship	O
product	O
,	O
Script	B-Operating_System
Debugger	I-Operating_System
.	O
</s>
<s>
This	O
improved	O
second	O
version	O
of	O
the	O
language	O
was	O
bundled	O
with	O
version	O
4	O
of	O
Script	B-Operating_System
Debugger	I-Operating_System
.	O
</s>
<s>
JavaScript	B-Application
OSA	I-Application
was	O
eventually	O
discontinued	O
due	O
to	O
lack	O
of	O
interest	O
and	O
was	O
dropped	O
from	O
Script	B-Operating_System
Debugger	I-Operating_System
5	O
in	O
2012	O
.	O
</s>
<s>
OS	B-Device
X	I-Device
Yosemite	I-Device
introduced	O
JavaScript	B-Language
for	O
Automation	O
(	O
JXA	O
)	O
:	O
system-wide	O
support	O
for	O
scripting	O
with	O
JavaScript	B-Language
,	O
built	O
upon	O
JavaScriptCore	O
and	O
the	O
Open	O
Scripting	O
Architecture	O
.	O
</s>
<s>
It	O
features	O
an	O
Objective-C	B-Language
bridge	O
which	O
enables	O
entire	O
Cocoa	B-Operating_System
applications	B-Application
to	O
be	O
programmed	O
in	O
JavaScript	B-Language
.	O
</s>
