<s>
TAC	B-Protocol
is	O
an	O
open	B-Application
source	I-Application
instant	B-Application
messaging	I-Application
and	O
chat	O
client	O
program	O
written	O
by	O
AOL	O
which	O
uses	O
the	O
TOC	B-Application
protocol	I-Application
used	O
by	O
the	O
AOL	B-Protocol
Instant	I-Protocol
Messenger	I-Protocol
system	O
.	O
</s>
<s>
It	O
is	O
written	O
in	O
Tcl	B-Operating_System
,	O
and	O
is	O
a	O
command	O
line	O
client	O
.	O
</s>
<s>
It	O
is	O
a	O
command	O
line	O
version	O
of	O
the	O
GUI	B-Application
TiK	B-Language
client	O
which	O
is	O
written	O
in	O
Tcl/Tk	B-Application
.	O
</s>
<s>
Developing	O
of	O
TAC	B-Protocol
and	O
TiK	B-Language
began	O
in	O
1998	O
.	O
</s>
<s>
The	O
name	O
TAC	B-Protocol
is	O
said	O
to	O
stand	O
for	O
"	O
TAC	B-Protocol
,	O
another	O
client	O
"	O
.	O
</s>
