<s>
DEMOS	B-Operating_System
(	O
Dialogovaya	O
Edinaya	O
Mobilnaya	O
Operatsionnaya	O
Sistema	O
:	O
)	O
is	O
a	O
Unix-like	B-Operating_System
operating	I-Operating_System
system	I-Operating_System
developed	O
in	O
the	O
Soviet	O
Union	O
.	O
</s>
<s>
It	O
is	O
derived	O
from	O
Berkeley	B-Operating_System
Software	I-Operating_System
Distribution	I-Operating_System
(	O
BSD	B-Operating_System
)	O
Unix	O
.	O
</s>
<s>
DEMOS	B-Operating_System
's	O
development	O
was	O
initiated	O
in	O
the	O
Kurchatov	O
Institute	O
of	O
Atomic	O
Energy	O
in	O
Moscow	O
in	O
1982	O
,	O
and	O
development	O
continued	O
in	O
cooperation	O
from	O
other	O
institutes	O
,	O
and	O
commercialized	O
by	O
DEMOS	B-Operating_System
Co-operative	O
which	O
employed	O
most	O
key	O
contributors	O
to	O
DEMOS	B-Operating_System
and	O
to	O
its	O
earlier	O
alternative	O
,	O
MNOS	B-Operating_System
(	O
a	O
clone	O
of	O
Version	B-Operating_System
6	I-Operating_System
Unix	I-Operating_System
)	O
.	O
</s>
<s>
MNOS	B-Operating_System
and	O
DEMOS	B-Operating_System
version	O
1.x	O
were	O
gradually	O
merged	O
from	O
1986	O
until	O
1990	O
,	O
leaving	O
the	O
joint	O
OS	O
,	O
DEMOS	B-Operating_System
version	O
2.x	O
,	O
with	O
support	O
for	O
different	O
Cyrillic	O
script	O
character	B-General_Concept
encoding	I-General_Concept
(	O
charsets	B-General_Concept
)	O
(	O
KOI-8	O
and	O
U-code	O
,	O
used	O
in	O
DEMOS	B-Operating_System
1	O
and	O
MNOS	B-Operating_System
,	O
respectively	O
)	O
.	O
</s>
<s>
Initially	O
it	O
was	O
developed	O
for	O
SM-4	B-Device
(	O
a	O
PDP-11/40	B-Device
clone	O
)	O
and	O
SM-1600	O
.	O
</s>
<s>
Later	O
it	O
was	O
ported	O
to	O
Elektronika-1082	O
,	O
BESM	B-Device
,	O
ES	B-Device
EVM	I-Device
,	O
clones	O
of	O
VAX-11	O
(	O
SM-1700	O
)	O
,	O
and	O
several	O
other	O
platforms	O
,	O
including	O
PC/XT	B-Device
,	O
Elektronika-85	O
(	O
a	O
clone	O
of	O
DEC	B-Device
Professional	I-Device
)	O
,	O
and	O
several	O
Motorola	O
68020-based	O
microcomputers	O
.	O
</s>
<s>
The	O
development	O
of	O
DEMOS	B-Operating_System
effectively	O
ceased	O
in	O
1991	O
,	O
when	O
the	O
second	O
project	O
of	O
the	O
DEMOS	B-Operating_System
team	O
,	O
RELCOM	O
,	O
took	O
priority	O
.	O
</s>
