What is Software
According to [IEEE Standard 610.12-1990] Software is Computer programs, procedures, and possibly associated documentation and data relates to the operation of a computer system.
What is Software Quality?
-Conformance to requirements
-Lack of bugs
-High reliability (number of failures per n hours of operation)
-Measured as Mean Time To Failure (MTTF)
Importance of Software Quality
-Software is a major component of computer systems
-(about 80% of the cost) – used for communication phone system,email system)
-Health monitoring,
-Transportation (e.g. automobile, aeronautics),
-Economic exchanges (e.g. e-commerce)
Software defects are extremely costly in term of
-money
-reputation
-loss of life
Some Causes of Software Errors
1. Client developer communication failures
2. Intentional variation from software requirements
3. Logical design errors
4. Coding errors
5. Noncompliance with documentation and coding instructions
6. Shortcomings of the testing process
7. User interface and procedure
8. Documentation errors fault
The Software Quality Challenge
-The uniqueness of the software product
-High complexity
-Limited opportunities to detect defects (“bugs”)