<s>
Record	B-Application
and	I-Application
replay	I-Application
debugging	I-Application
is	O
the	O
process	O
of	O
recording	O
the	O
execution	O
of	O
a	O
software	O
program	O
so	O
that	O
it	O
may	O
be	O
played	O
back	O
within	O
a	O
debugger	B-Application
to	O
help	O
diagnose	O
and	O
resolve	O
defects	O
.	O
</s>
<s>
The	O
concept	O
is	O
analogous	O
to	O
the	O
use	O
of	O
a	O
flight	B-Device
data	I-Device
recorder	I-Device
to	O
diagnose	O
the	O
cause	O
of	O
an	O
airplane	O
flight	O
malfunction	O
.	O
</s>
<s>
Record	O
and	O
replay	O
debuggers	B-Application
record	O
application	B-Application
state	I-Application
at	O
every	O
step	O
of	O
the	O
program	O
's	O
process	O
and	O
thread	O
execution	O
,	O
including	O
memory	O
interactions	O
,	O
deterministic	O
and	O
non-deterministic	O
inputs	O
,	O
system	O
resource	O
status	O
,	O
and	O
store	O
it	O
to	O
disk	O
in	O
a	O
log	O
.	O
</s>
<s>
Record	B-Application
and	I-Application
replay	I-Application
debugging	I-Application
is	O
particularly	O
useful	O
for	O
debugging	O
intermittent	O
and	O
non-deterministic	O
defects	O
,	O
which	O
can	O
be	O
difficult	O
to	O
reproduce	O
.	O
</s>
<s>
Record	B-Application
and	I-Application
replay	I-Application
debugging	I-Application
technology	O
is	O
often	O
fundamental	O
to	O
reverse	O
debugging	O
and	O
time	B-Application
travel	I-Application
debugging	I-Application
.	O
</s>
