<s>
Crash-only	B-Operating_System
software	I-Operating_System
refers	O
to	O
computer	B-Application
programs	I-Application
that	O
handle	O
failures	O
by	O
simply	O
restarting	O
,	O
without	O
attempting	O
any	O
sophisticated	O
recovery	O
.	O
</s>
<s>
Correctly	O
written	O
components	O
of	O
crash-only	B-Operating_System
software	I-Operating_System
can	O
microreboot	B-Operating_System
to	O
a	O
known-good	O
state	O
without	O
the	O
help	O
of	O
a	O
user	O
.	O
</s>
<s>
Crash-only	B-Operating_System
software	I-Operating_System
also	O
has	O
benefits	O
for	O
end-users	O
.	O
</s>
<s>
For	O
example	O
,	O
word	B-General_Concept
processors	I-General_Concept
usually	O
save	O
settings	O
when	O
they	O
are	O
closed	O
.	O
</s>
<s>
A	O
crash-only	B-Operating_System
application	O
is	O
designed	O
to	O
save	O
all	O
changed	O
user	O
settings	O
soon	O
after	O
they	O
are	O
changed	O
,	O
so	O
that	O
the	O
persistent	B-Library
state	I-Library
matches	O
that	O
of	O
the	O
running	O
machine	O
.	O
</s>
<s>
Erlang	B-Operating_System
is	O
a	O
computer	O
language	O
originally	O
built	O
by	O
Ericsson	O
for	O
fault-tolerant	O
telephone	O
switches	O
.	O
</s>
<s>
Programs	O
are	O
structured	O
as	O
modules	O
that	O
can	O
be	O
replaced	O
(	O
hot	B-Device
swapped	I-Device
)	O
without	O
having	O
to	O
restart	O
the	O
entire	O
program	O
.	O
</s>
<s>
Within	O
the	O
Open	B-Language
Telecom	I-Language
Platform	I-Language
,	O
which	O
often	O
is	O
used	O
together	O
with	O
Erlang	B-Operating_System
,	O
there	O
exist	O
frameworks	O
to	O
simplify	O
and	O
automate	O
this	O
task	O
.	O
</s>
