<s>
The	O
Apple	B-Operating_System
Type	I-Operating_System
Services	I-Operating_System
for	I-Operating_System
Unicode	I-Operating_System
Imaging	I-Operating_System
(	O
ATSUI	B-Operating_System
)	O
is	O
the	O
set	O
of	O
services	O
for	O
rendering	O
Unicode-encoded	O
text	O
introduced	O
in	O
Mac	B-Operating_System
OS	I-Operating_System
8.5	I-Operating_System
and	O
carried	O
forward	O
into	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
.	O
</s>
<s>
It	O
replaced	O
the	O
WorldScript	B-Operating_System
engine	O
for	O
legacy	O
encodings	O
.	O
</s>
<s>
ATSUI	B-Operating_System
was	O
replaced	O
by	O
a	O
faster	O
and	O
modern	O
Unicode	O
imaging	O
engine	O
called	O
Core	B-Operating_System
Text	I-Operating_System
in	O
Mac	B-Application
OS	I-Application
X	I-Application
10.5	I-Application
(	O
Leopard	B-Application
)	O
.	O
</s>
<s>
Programmers	O
are	O
instructed	O
to	O
replace	O
all	O
their	O
ATS	O
code	O
(	O
including	O
ATSUI	B-Operating_System
)	O
with	O
CoreText	B-Operating_System
as	O
ATS	O
functionality	O
will	O
be	O
completely	O
removed	O
in	O
future	O
releases	O
of	O
OS	O
X.	O
"	O
</s>
<s>
However	O
,	O
it	O
was	O
actually	O
removed	O
in	O
September	O
2022	O
for	O
source	O
code	O
targeting	O
only	O
macOS	B-Operating_System
13	I-Operating_System
Ventura	I-Operating_System
,	O
and	O
will	O
be	O
totally	O
removed	O
in	O
macOS	B-Operating_System
14	O
.	O
</s>
