<s>
iChat	B-Protocol
(	O
previously	O
iChat	B-Protocol
AV	I-Protocol
)	O
is	O
a	O
discontinued	O
instant	B-Application
messaging	I-Application
software	B-Application
application	I-Application
developed	O
by	O
Apple	O
Inc	O
.	O
for	O
use	O
on	O
its	O
Mac	B-Device
OS	I-Device
X	I-Device
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
It	O
supported	O
instant	O
text	O
messaging	O
over	O
XMPP/Jingle	O
or	O
OSCAR	B-Application
(	O
AIM	B-Protocol
)	O
protocol	O
,	O
audio	B-Application
and	O
video	B-Application
calling	I-Application
,	O
and	O
screen-sharing	O
capabilities	O
.	O
</s>
<s>
It	O
also	O
allowed	O
for	O
local	O
network	O
discussion	O
with	O
users	O
discovered	O
through	O
Bonjour	B-Application
protocols	I-Application
.	O
</s>
<s>
In	O
OS	B-Operating_System
X	I-Operating_System
10.8	I-Operating_System
Mountain	I-Operating_System
Lion	I-Operating_System
,	O
iChat	B-Protocol
was	O
replaced	O
by	O
Messages	B-Protocol
for	O
chat	O
and	O
FaceTime	B-Operating_System
for	O
video	B-Application
calling	I-Application
.	O
</s>
<s>
iChat	B-Protocol
was	O
first	O
released	O
in	O
August	O
2002	O
as	O
part	O
of	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
10.2	I-Operating_System
.	O
</s>
<s>
It	O
featured	O
integration	O
with	O
the	O
Address	O
Book	O
and	O
Mail	O
applications	O
and	O
was	O
the	O
first	O
officially	O
supported	O
AIM	B-Protocol
client	B-Protocol
that	O
was	O
native	O
to	O
Mac	B-Device
OS	I-Device
X	I-Device
(	O
the	O
first-party	O
AIM	B-Protocol
application	O
at	O
the	O
time	O
was	O
still	O
running	O
in	O
Classic	O
emulation	O
)	O
.	O
</s>
<s>
One	O
episode	O
of	O
the	O
first	O
season	O
of	O
the	O
HBO	O
dramedy	O
series	O
Entourage	O
had	O
Eric	O
Murphy	O
having	O
an	O
iChat	B-Protocol
conversation	O
with	O
Ari	O
Gold	O
,	O
marking	O
the	O
first	O
time	O
that	O
this	O
application	O
was	O
used	O
on	O
a	O
television	O
series	O
.	O
</s>
<s>
iChat	B-Protocol
incorporated	O
Apple	O
's	O
Aqua	B-Application
interface	I-Application
and	O
used	O
speech	O
bubbles	O
and	O
pictures	O
to	O
personify	O
the	O
online	O
chatting	O
experience	O
.	O
</s>
<s>
With	O
iChat	B-Protocol
,	O
green	O
(	O
available	O
)	O
,	O
yellow	O
(	O
idle	O
)	O
,	O
and	O
red	O
(	O
away	O
)	O
icons	O
could	O
be	O
displayed	O
next	O
to	O
the	O
name	O
of	O
each	O
connected	O
user	O
on	O
the	O
buddy	O
list	O
.	O
</s>
<s>
In	O
June	O
2003	O
,	O
Apple	O
announced	O
iChat	B-Protocol
AV	I-Protocol
,	O
the	O
second	O
major	O
version	O
of	O
iChat	B-Protocol
.	O
</s>
<s>
It	O
added	O
video	B-Application
and	O
audio	B-Application
conferencing	O
capabilities	O
based	O
on	O
the	O
industry-standard	O
Session	B-Application
Initiation	I-Application
Protocol	I-Application
(	O
SIP	O
)	O
.	O
</s>
<s>
The	O
final	O
version	O
of	O
the	O
software	O
was	O
shipped	O
with	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
10.3	I-Operating_System
and	O
became	O
available	O
separately	O
on	O
the	O
same	O
day	O
for	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
10.2	I-Operating_System
.	O
</s>
<s>
In	O
February	O
2004	O
,	O
AOL	O
introduced	O
AOL	B-Protocol
Instant	I-Protocol
Messenger	I-Protocol
(	O
AIM	B-Protocol
)	O
version	O
5.5	O
for	O
Windows	O
users	O
,	O
which	O
enabled	O
video	B-Application
,	O
but	O
not	O
audio	B-Application
,	O
chats	O
over	O
the	O
AIM	B-Protocol
protocol	O
and	O
was	O
compatible	O
with	O
Apple	O
's	O
iChat	B-Protocol
AV	I-Protocol
.	O
</s>
<s>
On	O
the	O
same	O
day	O
,	O
Apple	O
released	O
a	O
public	O
beta	O
of	O
iChat	B-Protocol
AV	I-Protocol
2.1	O
to	O
allow	O
Mac	B-Device
OS	I-Device
X	I-Device
users	O
to	O
video	B-Application
conferencing	I-Application
with	O
AIM	B-Protocol
5.5	O
users	O
.	O
</s>
<s>
In	O
June	O
2004	O
,	O
Steve	O
Jobs	O
announced	O
that	O
the	O
next	O
version	O
of	O
iChat	B-Protocol
AV	I-Protocol
would	O
be	O
included	O
with	O
Mac	B-Application
OS	I-Application
X	I-Application
10.4	I-Application
.	O
iChat	B-Protocol
AV	I-Protocol
3	O
provided	O
additional	O
support	O
to	O
allow	O
up	O
to	O
four	O
people	O
in	O
a	O
single	O
video	B-Application
conference	I-Application
and	O
ten	O
people	O
in	O
an	O
audio	B-Application
conference	O
.	O
</s>
<s>
Additionally	O
,	O
the	O
new	O
version	O
of	O
iChat	B-Protocol
used	O
the	O
H.264/AVC	B-Application
codec	O
,	O
which	O
offered	O
superior	O
quality	O
video	B-Application
compared	O
to	O
the	O
older	O
H.263	B-Algorithm
codec	O
used	O
in	O
previous	O
versions	O
.	O
</s>
<s>
This	O
release	O
supported	O
the	O
XMPP	B-Protocol
protocol	I-Protocol
,	O
which	O
could	O
be	O
directly	O
used	O
to	O
connect	O
to	O
Google	B-Application
Talk	I-Application
and	O
indirectly	O
be	O
used	O
to	O
connect	O
to	O
users	O
of	O
services	O
including	O
Facebook	O
Chat	O
,	O
and	O
Yahoo	B-Application
!	O
</s>
<s>
However	O
,	O
support	O
was	O
limited	O
as	O
it	O
did	O
not	O
support	O
several	O
common	O
XMPP	B-Protocol
features	O
such	O
as	O
account	O
creation	O
,	O
service	B-Protocol
discovery	I-Protocol
and	O
full	O
multi-user	O
chat	O
support	O
.	O
</s>
<s>
iChat	B-Protocol
3	O
included	O
the	O
Bonjour	B-Application
protocol	I-Application
(	O
previously	O
called	O
Rendezvous	O
)	O
which	O
allowed	O
iChat	B-Protocol
to	O
automatically	O
find	O
other	O
users	O
with	O
iChat	B-Protocol
Bonjour	B-Application
messaging	O
enabled	O
on	O
the	O
local	O
network	O
.	O
</s>
<s>
In	O
October	O
2005	O
,	O
iChat	B-Protocol
received	O
support	O
for	O
encrypted	O
communications	O
,	O
but	O
only	O
for	O
paid	O
subscribers	O
of	O
.Mac	B-Application
(	O
now	O
iCloud	B-Application
)	O
service	O
.	O
</s>
<s>
These	O
features	O
were	O
part	O
of	O
iChat	B-Protocol
3.1	O
,	O
released	O
as	O
part	O
of	O
the	O
Mac	B-Application
OS	I-Application
X	I-Application
v10.4.3	I-Application
update	O
.	O
</s>
<s>
This	O
version	O
also	O
added	O
support	O
for	O
XMPP	B-Protocol
multi-user	O
chat	O
.	O
</s>
<s>
In	O
March	O
2007	O
,	O
Apple	O
released	O
the	O
Mac	O
OS	O
X	O
v10.4.9	O
update	O
,	O
which	O
allowed	O
USB	B-Application
video	I-Application
device	I-Application
class	I-Application
(	O
UVC	O
)	O
cameras	O
to	O
be	O
used	O
with	O
iChat	B-Protocol
,	O
rather	O
than	O
FireWire	O
cameras	O
only	O
.	O
</s>
<s>
This	O
allowed	O
a	O
wider	O
range	O
of	O
cameras	O
to	O
be	O
used	O
with	O
iChat	B-Protocol
AV	I-Protocol
.	O
</s>
<s>
iChat	B-Protocol
4	O
was	O
introduced	O
as	O
a	O
part	O
of	O
Mac	B-Application
OS	I-Application
X	I-Application
10.5	I-Application
and	O
received	O
new	O
features	O
including	O
:	O
iChat	B-Protocol
Theater	O
(	O
inspired	O
by	O
ChatFX	O
a	O
product	O
from	O
Plum	O
Amazing	O
)	O
,	O
Backdrops	O
,	O
and	O
Screen	O
Sharing	O
.	O
</s>
<s>
iChat	B-Protocol
Theater	O
allowed	O
users	O
to	O
share	O
any	O
file	O
supported	O
by	O
Quick	B-Operating_System
Look	I-Operating_System
,	O
including	O
photos	O
,	O
Keynote	O
presentations	O
,	O
and	O
movies	O
,	O
over	O
a	O
video	B-Application
chat	I-Application
session	O
.	O
</s>
<s>
Backdrops	O
allowed	O
users	O
to	O
insert	O
movies	O
or	O
photos	O
as	O
a	O
backdrop	O
in	O
video	B-Application
chats	I-Application
.	O
</s>
<s>
Screen	O
Sharing	O
allowed	O
two	O
users	O
of	O
Mac	B-Application
OS	I-Application
X	I-Application
Leopard	I-Application
to	O
have	O
control	O
of	O
the	O
same	O
desktop	O
and	O
work	O
collaboratively	O
.	O
</s>
<s>
Minor	O
features	O
in	O
the	O
new	O
release	O
included	O
multiple	O
logins	O
,	O
animated	O
icons	O
,	O
use	O
of	O
Photo	B-Application
Booth	I-Application
effects	O
in	O
live	O
video	B-Application
chat	I-Application
,	O
and	O
tabbed	O
chats	O
.	O
</s>
<s>
iChat	B-Protocol
5.0	O
,	O
released	O
with	O
Mac	B-Device
OS	I-Device
X	I-Device
10.6	I-Device
,	O
reduced	O
the	O
bandwidth	O
required	O
for	O
640×480	O
video	B-Application
chats	I-Application
and	O
upgraded	O
iChat	B-Protocol
Theater	O
to	O
the	O
same	O
resolution	O
.	O
</s>
<s>
iChat	B-Protocol
6.0	O
,	O
released	O
with	O
Mac	B-Application
OS	I-Application
X	I-Application
10.7	I-Application
,	O
added	O
support	O
for	O
Yahoo	B-Application
Messenger	I-Application
account	O
and	O
allowed	O
iChat	B-Protocol
users	O
to	O
have	O
text	O
,	O
voice	O
and	O
video	B-Application
chats	I-Application
using	O
their	O
Yahoo	B-Application
Mail	O
accounts	O
.	O
</s>
<s>
iChat	B-Protocol
6	O
was	O
the	O
last	O
iChat	B-Protocol
version	O
;	O
in	O
OS	B-Operating_System
X	I-Operating_System
Mountain	I-Operating_System
Lion	I-Operating_System
,	O
it	O
was	O
replaced	O
by	O
Messages	B-Protocol
.	O
</s>
<s>
The	O
final	O
release	O
,	O
iChat	B-Protocol
6.0.1	O
,	O
was	O
published	O
on	O
February	O
1	O
,	O
2012	O
.	O
</s>
<s>
As	O
part	O
of	O
the	O
OS	B-Operating_System
X	I-Operating_System
Mountain	I-Operating_System
Lion	I-Operating_System
preview	O
,	O
Apple	O
announced	O
on	O
February	O
16	O
,	O
2012	O
,	O
that	O
its	O
OS	B-Application
X	I-Application
messaging	O
client	B-Protocol
would	O
be	O
Messages	B-Protocol
,	O
and	O
that	O
it	O
would	O
support	O
the	O
iMessage	O
protocol	O
,	O
making	O
it	O
compatible	O
with	O
the	O
iOS	O
client	B-Protocol
.	O
</s>
<s>
Messages	B-Protocol
also	O
incorporates	O
FaceTime	B-Operating_System
support	O
.	O
</s>
<s>
Apple	O
made	O
Messages	B-Protocol
immediately	O
available	O
as	O
a	O
downloadable	O
beta	O
version	O
for	O
use	O
on	O
Mac	B-Application
OS	I-Application
X	I-Application
10.7	I-Application
.	O
</s>
<s>
iChat	B-Protocol
's	O
AIM	B-Protocol
support	O
was	O
fully	O
endorsed	O
by	O
AOL	O
,	O
and	O
used	O
their	O
official	O
implementation	O
of	O
the	O
AIM	B-Protocol
OSCAR	B-Application
protocol	I-Application
.	O
</s>
<s>
Using	O
a	O
XMPP	B-Protocol
transport	O
,	O
iChat	B-Protocol
could	O
serve	O
as	O
a	O
client	B-Protocol
for	O
AOL	B-Protocol
Instant	I-Protocol
Messenger	I-Protocol
,	O
Yahoo	B-Application
!	O
</s>
<s>
Messenger	O
,	O
MobileMe	B-Application
,	O
ICQ	B-Protocol
and	O
XMPP	B-Protocol
.	O
</s>
<s>
iChat	B-Protocol
could	O
also	O
integrate	O
Google	B-Application
Talk	I-Application
contacts	O
into	O
the	O
XMPP	B-Protocol
pane	O
.	O
</s>
