This document discusses software quality and its key factors. It defines software quality as meeting customer requirements, continuously improving processes, and removing defects. Quality factors are categorized into product operation, revision, and transition. Product operation factors include correctness, reliability, efficiency, integrity, and usability. Revision factors like maintainability and testability contribute to easy product changes. Transition factors like interoperability concern exchanging data between systems. Quality factors can be indifferent, complementary, or conflicting. They are measured using a framework of factors, criteria, and metrics. Technical metrics collected during development help improve quality, while after-the-fact metrics summarize quality after a project.

1. Basic Concept
of Software
Quality

2. BY: Adeel Rasheed

3. Quality
o Some key points from various definitions of
quality are as follows.
o Meeting explicit as well as implicit
customer requirements
o Continually improving the software process
o Removing defects throughout the process
o Developing a product that is fit for use

4. What is software quality?
What are software quality factors?
To build quality software products, the Quality
requirements of a product need to be clearly defined
so that software engineering can aim to achieve them.
The quality requirements of a product being developed
can be specified in terms of the quality factors.

5. Categories of quality
factors
Product operation
Product revision
Product transition

6. Product Pperation
The product operation category includes
factors that help us to Understand the
operational characteristics of a product. The
factors in this category are:
 Correctness
 Reliability
 Efficiency
 Integrity
 Usability

7. Product Revision
 What is product revision?
 •The product revision category of framework includes
the factors that contribute to ease in revising a product
These are:
 Maintainability
 Testability
 Flexibility
 •If a product cannot be revised easily, then:
 Enhancements cannot be made to meet the changing
requirements.
 Defects cannot be fixed or are very costly to fix.
 Any changes made might add more defects.

8. Product Transition
Interoperability
•McCall defines interoperability as the effort
required to couple one system to another
•Interoperability is concerned with the exchange
of data and services between systems.

9. Types of relationship
between quality factors
 Indifferent .
 Complementary.
 Conflicting.

10. Measuring quality factors
Software quality Factors that are management-
and user-oriented
Software-oriented attributes or criteria
 Metrics for these attributes
The framework is also called F-C-M (factor-
criteria-metric) because of this structure.

11. Errors and Defects
 •Defects are the problems that are found either by the
customer or by the software professionals after a product
as been delivered.
 •Defects lower the customer perspective on product
quality.
 We use the term 'error' for the problems that are found
using formal processes but are detected before the
delivery of a product to the customer.

12. Categories of metrics for
quality
 Technical metrics
 After-the-fact metrics

13. Technical metrics enable action in time
•Technical metrics are based on measures of the
technical attributes of a product made by software
engineers as part of the software process.
•Technical metrics provide a good understanding of
the technical quality of the product while it is being
made.
•Software engineers use technical metrics to improve
the way they work and to create better design and
code.
Technical Metrics

14. After-the-fact metrics
 •After-the-fact metrics are based on the measures
made at the end of a project.
 •They are simple summary metrics and are usually
relatively easy to collect.
 •They are based on the measures visible to
managers and do not require technical insight into
the process.