<s>
DOS	B-Application
Shell	I-Application
is	O
a	O
file	B-Application
manager	I-Application
that	O
debuted	O
in	O
MS-DOS	B-Application
and	O
PC	O
DOS	O
version	O
4.0	O
,	O
released	O
in	O
June	O
1988	O
.	O
</s>
<s>
It	O
was	O
discontinued	O
in	O
MS-DOS	B-Application
version	O
6.22	O
,	O
but	O
remained	O
part	O
of	O
the	O
Supplemental	O
Disk	O
.	O
</s>
<s>
The	O
Supplemental	O
Disk	O
could	O
be	O
ordered	O
or	O
could	O
be	O
downloaded	O
through	O
Microsoft	O
's	O
FTP	B-Protocol
server	O
.	O
</s>
<s>
DOS	B-Application
Shell	I-Application
was	O
retained	O
in	O
PCDOS	O
until	O
PC	O
DOS	O
2000	O
.	O
</s>
<s>
DOS	B-Application
Shell	I-Application
was	O
one	O
of	O
the	O
first	O
successful	O
attempts	O
to	O
create	O
a	O
basic	O
graphical	B-Application
user	I-Application
interface	I-Application
(	O
GUI	B-Application
)	O
type	O
file	B-Application
manager	I-Application
in	O
DOS	O
,	O
although	O
it	O
is	O
properly	O
referred	O
to	O
as	O
a	O
text	B-Application
user	I-Application
interface	I-Application
(	O
TUI	O
)	O
or	O
Character-Oriented	O
Windows	O
(	O
COW	O
)	O
even	O
though	O
graphical	O
modes	O
were	O
available	O
on	O
supported	O
hardware	O
(	O
VGA-equipped	O
PCs	O
)	O
.	O
</s>
<s>
The	O
shell	O
is	O
very	O
much	O
like	O
a	O
DOS	O
version	O
of	O
File	B-Application
Manager	I-Application
found	O
in	O
Windows	O
up	O
to	O
versions	O
3.11	O
and	O
NT	B-Device
3.51	I-Device
,	O
and	O
File	B-Protocol
Explorer	I-Protocol
on	O
later	O
versions	O
.	O
</s>
<s>
An	O
early	O
incarnation	O
of	O
DOS	B-Application
Shell	I-Application
,	O
titled	O
MS-DOS	B-Application
Manager	O
,	O
was	O
bundled	O
exclusively	O
with	O
the	O
Eazy	B-Device
PC	I-Device
,	O
an	O
IBM	O
PC	O
clone	O
manufactured	O
by	O
Zenith	O
Data	O
Systems	O
in	O
1987	O
.	O
</s>
<s>
In	O
MS-DOS	B-Application
4.x	O
and	O
5.x	O
,	O
the	O
program	O
was	O
implemented	O
as	O
COM	O
file	O
(	O
DOSSHELL.COM	B-Application
)	O
.	O
</s>
<s>
In	O
MS-DOS	B-Application
6	O
the	O
executable	O
had	O
an	O
.EXE	O
filename	O
extension	O
(	O
DOSSHELL.EXE	B-Application
)	O
.	O
</s>
<s>
The	O
shell	O
includes	O
common	O
features	O
seen	O
in	O
other	O
file	B-Application
managers	I-Application
such	O
as	O
copying	O
,	O
moving	O
and	O
renaming	O
files	O
as	O
well	O
as	O
the	O
ability	O
to	O
launch	O
applications	O
with	O
a	O
double-click	O
.	O
</s>
<s>
The	O
shell	O
could	O
be	O
run	O
by	O
the	O
command	B-Application
"	O
DOSSHELL	B-Application
"	O
.	O
</s>
<s>
Like	O
many	O
modern	O
file	B-Application
managers	I-Application
,	O
it	O
had	O
the	O
ability	O
to	O
display	O
dual	O
hierarchy	O
directory	O
and	O
file	O
lists	O
,	O
i.e.	O
</s>
<s>
A	O
mouse	B-Device
was	O
supported	O
,	O
however	O
,	O
like	O
any	O
other	O
DOS	O
application	O
,	O
it	O
required	O
an	O
appropriate	O
device	B-Application
driver	I-Application
.	O
</s>
<s>
DOS	B-Application
Shell	I-Application
was	O
incapable	O
of	O
full	O
multitasking	B-Operating_System
.	O
</s>
<s>
It	O
supported	O
rudimentary	O
task	O
switching	O
;	O
it	O
could	O
switch	O
between	O
programs	O
running	O
in	O
memory	B-Architecture
,	O
at	O
the	O
cost	O
of	O
performance	O
hit	O
.	O
</s>
<s>
However	O
,	O
all	O
the	O
running	O
programs	O
had	O
to	O
fit	O
into	O
conventional	B-Device
memory	I-Device
area	O
,	O
as	O
there	O
was	O
no	O
support	O
for	O
swapping	O
to	O
disk	O
.	O
</s>
<s>
In	O
time	O
,	O
Windows	B-Application
3.1x	I-Application
,	O
with	O
its	O
own	O
graphical	B-Application
user	I-Application
interface	I-Application
,	O
became	O
much	O
more	O
popular	O
among	O
computer	O
users	O
.	O
</s>
<s>
Windows	O
was	O
capable	O
of	O
multitasking	B-Operating_System
.	O
</s>
<s>
System	O
performance	O
was	O
much	O
higher	O
,	O
with	O
complete	O
access	O
to	O
extended	B-Device
memory	I-Device
.	O
</s>
