<s>
The	O
W3C	B-Language
Geolocation	I-Language
API	I-Language
is	O
an	O
effort	O
by	O
the	O
World	O
Wide	O
Web	O
Consortium	O
(	O
W3C	O
)	O
to	O
standardize	O
an	O
interface	O
to	O
retrieve	O
the	O
geographical	B-Application
location	I-Application
information	I-Application
for	O
a	O
client-side	O
device	O
.	O
</s>
<s>
It	O
defines	O
a	O
set	O
of	O
objects	O
,	O
ECMAScript	B-Language
standard	O
compliant	O
,	O
that	O
executing	O
in	O
the	O
client	O
application	O
give	O
the	O
client	O
's	O
device	O
location	O
through	O
the	O
consulting	O
of	O
Location	B-Protocol
Information	I-Protocol
Servers	I-Protocol
,	O
which	O
are	O
transparent	O
for	O
the	O
application	B-Application
programming	I-Application
interface	I-Application
(	O
API	B-Application
)	O
.	O
</s>
<s>
The	O
most	O
common	O
sources	O
of	O
location	O
information	O
are	O
IP	B-Protocol
address	I-Protocol
,	O
Wi-Fi	O
and	O
Bluetooth	B-Protocol
MAC	O
address	O
,	O
radio-frequency	B-Application
identification	I-Application
(	O
RFID	B-Application
)	O
,	O
Wi-Fi	O
connection	O
location	O
,	O
or	O
device	O
Global	O
Positioning	O
System	O
(	O
GPS	O
)	O
and	O
GSM/CDMA	O
cell	O
IDs	O
.	O
</s>
<s>
The	O
result	O
of	O
W3C	B-Language
Geolocation	I-Language
API	I-Language
will	O
usually	O
give	O
4	O
location	O
properties	O
,	O
including	O
latitude	O
and	O
longitude	O
(	O
coordinates	O
)	O
,	O
altitude	O
(	O
height	O
)	O
,	O
and	O
accuracy	O
[	O
of	O
the	O
position	O
gathered ]	O
,	O
which	O
all	O
depend	O
on	O
the	O
location	O
sources	O
.	O
</s>
<s>
Web	O
pages	O
can	O
use	O
the	O
Geolocation	B-Language
API	I-Language
directly	O
if	O
the	O
web	O
browser	O
implements	O
it	O
.	O
</s>
<s>
Historically	O
,	O
some	O
browsers	O
could	O
gain	O
support	O
via	O
the	B-Application
Google	I-Application
Gears	B-Application
plugin	B-Application
,	O
but	O
this	O
was	O
discontinued	O
in	O
2010	O
and	O
the	O
server-side	O
API	B-Application
it	O
depended	O
on	O
stopped	O
responding	O
in	O
2012	O
.	O
</s>
<s>
The	O
Geolocation	B-Language
API	I-Language
is	O
ideally	O
suited	O
to	O
web	O
applications	O
for	O
mobile	O
devices	O
such	O
as	O
personal	B-Application
digital	I-Application
assistants	I-Application
(	O
PDA	B-Application
)	O
and	O
smartphones	B-Application
.	O
</s>
<s>
On	O
desktop	O
computers	O
,	O
the	O
W3C	B-Language
Geolocation	I-Language
API	I-Language
works	O
in	O
Firefox	B-Application
since	O
version	O
3.5	O
,	O
Google	B-Application
Chrome	I-Application
,	O
Opera	B-Application
10.6	O
,	O
Internet	B-Application
Explorer	I-Application
9.0	O
,	O
and	O
Safari	O
5	O
.	O
</s>
<s>
On	O
mobile	O
devices	O
,	O
it	O
works	O
on	O
Android	B-Application
(	O
firmware	O
2.0	O
+	O
)	O
,	O
iOS	B-Operating_System
,	O
Windows	B-Protocol
Phone	I-Protocol
and	O
Maemo	B-Operating_System
.	O
</s>
<s>
The	O
W3C	B-Language
Geolocation	I-Language
API	I-Language
is	O
also	O
supported	O
by	O
Opera	B-Language
Mobile	I-Language
10.1	O
–	O
available	O
for	O
Android	B-Application
and	O
Symbian	B-Operating_System
devices	O
(	O
S60	O
generations	O
3	O
&	O
5	O
)	O
since	O
24	O
November	O
2010	O
.	O
</s>
<s>
Browsers	O
initially	O
allowed	O
access	O
to	O
the	O
API	B-Application
in	O
insecure	O
contexts	O
,	O
but	O
in	O
the	O
context	O
of	O
Secure	O
Contexts	O
,	O
browsers	O
,	O
e.g.	O
,	O
Chrome	B-Application
,	O
now	O
generally	O
require	O
a	O
secure	O
connection	O
.	O
</s>
<s>
Google	B-Application
Gears	I-Application
provided	O
geolocation	O
support	O
for	O
older	O
and	O
non-compliant	O
browsers	O
,	O
including	O
Internet	B-Application
Explorer	I-Application
7.0	O
+	O
as	O
a	O
Gears	B-Application
plugin	B-Application
,	O
and	O
Google	B-Application
Chrome	I-Application
which	O
implemented	O
Gears	B-Application
natively	O
.	O
</s>
<s>
It	O
also	O
supported	O
geolocation	O
on	O
mobile	O
devices	O
as	O
a	O
plugin	B-Application
for	O
the	O
Android	B-Application
browser	O
(	O
pre	O
version	O
2.0	O
)	O
and	O
Opera	B-Language
Mobile	I-Language
for	O
Windows	B-Operating_System
Mobile	I-Operating_System
.	O
</s>
<s>
However	O
,	O
the	B-Application
Google	I-Application
Gears	B-Application
Geolocation	B-Language
API	I-Language
is	O
incompatible	O
with	O
the	O
W3C	B-Language
Geolocation	I-Language
API	I-Language
and	O
is	O
no	O
longer	O
supported	O
.	O
</s>
<s>
The	O
Geolocation	B-Language
API	I-Language
does	O
not	O
provide	O
the	O
location	O
information	O
.	O
</s>
<s>
The	O
location	O
information	O
is	O
obtained	O
by	O
a	O
device	O
(	O
such	O
as	O
a	O
smartphone	B-Application
,	O
PC	O
or	O
modem	O
)	O
,	O
which	O
is	O
then	O
served	O
by	O
the	O
API	B-Application
to	O
be	O
brought	O
in	O
browser	O
.	O
</s>
<s>
A	O
smartphone	B-Application
with	O
GPS	O
capabilities	O
and	O
set	O
to	O
high	O
accuracy	O
mode	O
will	O
be	O
likely	O
to	O
obtain	O
the	O
location	O
data	O
from	O
this	O
.	O
</s>
<s>
It	O
has	O
the	O
highest	O
accuracy	O
;	O
in	O
most	O
Android	B-Application
smartphones	B-Application
,	O
the	O
accuracy	O
can	O
be	O
up	O
to	O
10	O
metres	O
.	O
</s>
<s>
Some	O
Wi-Fi	O
spots	O
have	O
location	B-Application
services	I-Application
capabilities	O
.	O
</s>
<s>
IP	B-Application
Address	I-Application
Location	I-Application
Location	O
is	O
detected	O
based	O
on	O
the	O
nearest	O
public	O
IP	B-Protocol
address	I-Protocol
on	O
a	O
device	O
(	O
which	O
can	O
be	O
a	O
computer	O
,	O
the	O
router	O
it	O
is	O
connected	O
to	O
,	O
or	O
the	O
Internet	O
Service	O
Provider	O
(	O
ISP	O
)	O
the	O
router	O
uses	O
)	O
.	O
</s>
<s>
The	O
location	O
depends	O
on	O
the	O
IP	O
information	O
available	O
,	O
but	O
in	O
many	O
cases	O
where	O
the	O
IP	O
is	O
hidden	O
behind	O
an	O
ISP	O
network	B-Protocol
address	I-Protocol
translation	I-Protocol
,	O
the	O
accuracy	O
is	O
only	O
to	O
the	O
level	O
of	O
a	O
city	O
,	O
region	O
or	O
even	O
country	O
.	O
</s>
<s>
Though	O
the	O
implementation	O
is	O
not	O
specified	O
,	O
W3C	B-Language
Geolocation	I-Language
API	I-Language
is	O
built	O
on	O
extant	O
technologies	O
,	O
and	O
is	O
heavily	O
influenced	O
by	O
Google	B-Application
Gears	I-Application
Geolocation	B-Language
API	I-Language
.	O
</s>
<s>
Example	O
:	O
Firefox	B-Application
's	O
Geolocation	O
implementation	O
uses	O
Google	B-Application
's	I-Application
network	O
location	O
provider	O
.	O
</s>
<s>
Google	B-Application
Gears	I-Application
Geolocation	O
works	O
by	O
sending	O
a	O
set	O
of	O
parameters	O
that	O
could	O
give	O
a	O
hint	O
as	O
to	O
where	O
the	O
user	O
's	O
physical	O
location	O
is	O
to	O
a	O
network	O
location	O
provider	O
server	O
,	O
which	O
is	O
by	O
default	O
the	O
one	O
provided	O
by	O
Google	B-Application
(	O
code.l.google.com	O
)	O
.	O
</s>
<s>
These	O
parameters	O
are	O
encapsulated	O
into	O
a	O
JavaScript	B-General_Concept
Object	I-General_Concept
Notation	I-General_Concept
(	O
JSON	B-General_Concept
)	O
message	O
and	O
sent	O
to	O
the	O
network	O
location	O
provider	O
via	O
HTTP	O
POST	O
.	O
</s>
<s>
Simple	O
JavaScript	B-Language
code	O
that	O
checks	O
if	O
the	O
browser	O
has	O
the	O
Geolocation	B-Language
API	I-Language
implemented	O
and	O
then	O
uses	O
it	O
to	O
get	O
the	O
current	O
position	O
of	O
the	O
device	O
.	O
</s>
