<s>
Perfect	B-Operating_System
Writer	I-Operating_System
is	O
a	O
word	B-General_Concept
processor	I-General_Concept
computer	B-Application
program	I-Application
published	O
by	O
Perfect	O
Software	O
for	O
CP/M	B-Application
,	O
subsequently	O
rewritten	O
and	O
released	O
as	O
Perfect	O
II	O
by	O
Thorn	O
EMI	O
Computer	O
Software	O
for	O
IBM	O
PC	O
compatible	O
computers	O
.	O
</s>
<s>
It	O
was	O
written	O
in	O
C	B-Language
and	O
famous	O
for	O
its	O
stability	O
.	O
</s>
<s>
It	O
was	O
an	O
enhanced	O
version	O
of	O
MINCE	B-Operating_System
,	O
which	O
itself	O
was	O
a	O
version	O
of	O
Emacs	B-Application
for	O
microcomputer	O
platforms	O
.	O
</s>
<s>
Emacs	B-Application
itself	O
was	O
too	O
heavyweight	O
to	O
fit	O
within	O
the	O
64kb	O
RAM	O
limit	O
of	O
most	O
microcomputers	O
.	O
</s>
<s>
Like	O
MINCE	B-Operating_System
,	O
it	O
included	O
a	O
floppy	B-Device
disk	I-Device
based	O
virtual	B-Architecture
memory	I-Architecture
system	O
.	O
</s>
<s>
Along	O
with	O
its	O
companion	O
spreadsheet	O
(	O
Perfect	O
Calc	O
)	O
,	O
and	O
database	O
(	O
Perfect	O
Filer	O
)	O
,	O
Perfect	B-Operating_System
Writer	I-Operating_System
was	O
bundled	O
with	O
early	O
Kaypro	O
II	O
and	O
Morrow	B-Device
computers	O
,	O
as	O
well	O
as	O
with	O
the	O
Torch	O
Computers	O
Z80	O
Disk	O
Pack	O
add-on	O
for	O
the	O
BBC	B-Device
Micro	I-Device
and	O
had	O
a	O
list	O
price	O
of	O
.	O
</s>
<s>
In	O
the	O
UK	O
,	O
it	O
was	O
bundled	O
with	O
the	O
short	O
lived	O
Advance	B-Device
86B	I-Device
PC	O
(	O
a	O
near	O
IBM	O
compatible	O
)	O
.	O
</s>
<s>
It	O
supported	O
up	O
to	O
7	O
buffers	O
,	O
had	O
a	O
character	O
transpose	O
command	O
,	O
undo	B-Application
,	O
footnotes	O
,	O
and	O
indexing	B-Data_Structure
.	O
</s>
<s>
Its	O
capabilities	O
were	O
very	O
close	O
to	O
that	O
of	O
the	O
dedicated	B-General_Concept
word	I-General_Concept
processors	I-General_Concept
of	O
the	O
day	O
.	O
</s>
<s>
Perfect	B-Operating_System
Writer	I-Operating_System
's	O
ability	O
to	O
cut	B-General_Concept
and	I-General_Concept
paste	I-General_Concept
between	O
documents	O
open	O
in	O
multiple	O
buffers	O
was	O
an	O
advantage	O
over	O
WordStar	B-Application
.	O
</s>
<s>
Perfect	B-Operating_System
Writer	I-Operating_System
supported	O
a	O
number	O
of	O
add-on	O
programs	O
,	O
Perfect	O
Speller	O
and	O
Perfect	O
Thesaurus	O
,	O
also	O
published	O
by	O
Perfect	O
Software	O
,	O
along	O
with	O
third	O
party	O
software	O
such	O
as	O
Plu*Perfect	O
published	O
by	O
Plu*Perfect	O
Systems	O
.	O
</s>
<s>
Plu*Perfect	O
included	O
"	O
D	O
"	O
,	O
a	O
dired-like	O
file	B-Application
browser	I-Application
that	O
was	O
deemed	O
"	O
the	O
best	O
of	O
all	O
directory	O
displayers	O
"	O
by	O
Stewart	O
Brand	O
.	O
</s>
<s>
Perfect	B-Operating_System
Writer	I-Operating_System
was	O
originally	O
published	O
by	O
Perfect	O
Software	O
.	O
</s>
