<s>
Program	B-General_Concept
comprehension	I-General_Concept
(	O
also	O
program	B-General_Concept
understanding	I-General_Concept
or	O
 [ source ] 	O
code	O
comprehension	O
)	O
is	O
a	O
domain	O
of	O
computer	O
science	O
concerned	O
with	O
the	O
ways	O
software	B-General_Concept
engineers	I-General_Concept
maintain	O
existing	O
source	O
code	O
.	O
</s>
<s>
Program	B-General_Concept
Comprehension	I-General_Concept
During	O
Software	O
Maintenance	O
and	O
Evolution	O
.	O
</s>
<s>
Computer	O
scientists	O
pioneering	O
program	B-General_Concept
comprehension	I-General_Concept
include	O
Ruven	O
Brooks	O
,	O
Ted	O
J	O
.	O
Biggerstaff	O
,	O
and	O
Anneliese	O
von	O
Mayrhauser	O
.	O
</s>
