Software Engineering

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CHAPTER 6 
Impediments to Software Design
that can be converted into a machine-readable format. At the computer processor 
level, these instructions are encoded as positive and negative electrical charges that 
denote binary values (0 and 1 to denote an on/off state, respectively). The com-
puter processor performs a variety of basic mathematical calculations to convert 
data values. The computer operating system provides the management of computa-
tional execution and the software product’s interaction with computer input/output 
devices and data storage equipment.
Computer science is a field of study that provides a research and development 
thrust to promote advances in programming languages and computational theory. 
Computational complexity theory investigates fundamental properties of data pro-
cessing algorithms that are highly abstract, while other branches of computer science, 
such as computer graphics, emphasize real-world applications. The study of program-
ming investigates the definition and structure of software languages to address com-
plex data processing transactions. Computer science research often intersects other 
disciplines, such as linguistics, mathematics, physics, statistics, and logic. 
However, 
there has been a paltry amount of attention paid to establishing a dependable 
approach to the design or engineering of software products.
 Most of the research has 
been relegated to low-level programmatic design heuristics. The 
Encarta Dictionary
 
defines 
heuristics
 as “a method of problem solving for which no formula exists, based 
on informal methods or experience, and employing a form of trial and error iteration.”
The development of software products with early programming languages 
began with simple problem solving heuristics. This approach was supplemented by 
a flow-charting technique used to describe the sequence of data processing actions 
necessary to perform a computational function or procedure. As a technique, flow 
charts were useful to identify control mechanisms (decision blocks and control 
flow), input/output procedures, data processing steps (e.g., 
X
=
X
+
1), calls to sub-
routines (typically detailed in a separate flow chart), and data processing concur-
rency. The use of flow charts lost favor in the early 1980s due to the undesirable use 
of 
goto(s)
 to describe arbitrary jumps in control flow. This resulted in “spaghetti” 
code, which made understanding data processing flow difficult and impacted the 
software maintenance challenge. However, the use of 
goto(s)
 was purely a result of 
unstructured programming or improper programmatic design techniques.
Software is a very broad term used to identify a variety of computer programs 
that operate computers and devices embedded with computer technologies. The term 
hardware
 is used to describe the physical elements of a system or computer-based 
system, while 
software
 refers to various types of programs or applications used to 
operate a computer-based system. Software code is a set of instructions that can be 
converted into a format that a computer can perform. Code is broken into procedures, 
routines, functions, modules, objects, or other constructs to form parts or elements of 
a larger program. This partitioning of data processing transactions originated due to 
the challenge with the ever-increasing size and complexity of computer programs.
Within the software domain, there are references to a variety of terms that must 
be clarified to distinguish some basic properties of software. 
Table 6.2
 provides a 
general explanation of these software product–related terms.

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