The fault classification describes the cause of the fault/failure that was
observed.
<P>
After considerable research, we have selected and modified terms
principally from these sources: 
<BR>
IBM's Ram Chillarege, "Orthogonal Defect Classification;" 
IEEE Standard. 1044 Standard Classification for Software Anomalies;
George Stark, The MITRE Corporation;
Boris Beizer, <I>Software Testing Techniques</I>. 
Examples are not inclusive, for lack of space, but should provide enough
information for selection:
<TABLE>
<TR><TD Colspan=2><HR>
<TR><TD>Specification/ Function:
<TD>Affects significant capability, end-user features,
product application programming interface (API), interfaces with hardware
architecture, global structures. Requirements Specification incorrect/
inadequate
<TR><TD Colspan=2><HR>
<TR><TD>Interface:
<TD>Corresponds to errors in interacting with other components
(software, hardware, user/database), modules, device drivers, call
statements, control blocks, parameter lists. 
<TR><TD Colspan=2><HR>
<TR><TD>Data Handling:
<TD>Data file not available; data referenced out-of bounds;
data initialization; variable used as flag or index not set properly; data
not properly defined / dimensioned; subscripting error; initialization, data
structure
<TR><TD Colspan=2><HR>
<TR><TD>Logic/ checking:
<TD>Addresses program logic that has failed to properly
validate data and values before they are used, loop conditions; omitted
cases; neglected extreme conditions; iterating loop incorrectly; 
<TR><TD Colspan=2><HR>
<TR><TD>Computational / algorithm:
<TD>Incorrect operand in equation; Incorrect
variables in algorithms; incorrect punctuation; rounding or truncation
errors; efficiency or correctness problems that can affect the task and can
be fixed without design change; missing computation
<TR><TD Colspan=2><HR>
<TR><TD>Performance / timing:
<TD>Time limit exceeded; storage limit exceeded; code or
design inefficient; network efficiency
<TR><TD Colspan=2><HR>
<TR><TD>Input:
<TD>Incorrect format; input read from incorrect location; end-of-file
missing or improperly encountered; incorrect data used for test cases
<TR><TD Colspan=2><HR>
<TR><TD>Output:
<TD>Data written to different location; incorrect format; incorrect
expected values for testing; presentation
<TR><TD Colspan=2><HR>
<TR><TD>Documentation:
<TD>Errors can affect all publications and maintenance notes,
and comments within design and code; presentation; ambiguous statement;
incomplete; redundant; incorrect; not traceable
<TR><TD Colspan=2><HR>
<TR><TD>Operation:
<TD>COTS software changes; configuration control
<TR><TD Colspan=2><HR>
<TR><TD>Improvement / Enhancement:
<TD>Improve existing functions; improve interfaces;
improve efficiency; improve usability   
<TR><TD Colspan=2><HR>
<TR><TD>Build/package/ merge
<TD>Errors that occur due to mistakes in library systems,
management of changes, or version control.
<TR><TD Colspan=2><HR>
</TABLE>