WEEK 3: SOFTWARE FUNDAMENTALS

Software

A generic set of instructions, programs, data, or scripts used to operate computers and execute specific tasks.

ISO 9126

An international standard for software assessment dividing quality into quality model, external metrics, internal metrics, and quality in use metrics.

Functionality

A software quality characteristic describing the performance of the software contrary to its intended purpose.

Suitability

A functionality sub-characteristic relating to the appropriateness and accessibility specifications of the software.

Accurateness

A functionality sub-characteristic concerning the accuracy of application functions and calculation results.

Interoperability

A functionality sub-characteristic concerning the ability of a software component to communicate with other modules or systems.

Compliance (Functionality)

A functionality sub-characteristic describing software conformity to business or government rules and standards.

Security

A functionality sub-characteristic referring to the prevention of unauthorized or improper access to program features.

Reliability

A software characteristic describing the ability to deliver required capabilities under specified restrictions.

Maturity

A reliability sub-characteristic concerning the extent and frequency of software malfunctions.

Fault Tolerance

A reliability sub-characteristic measuring the software's ability to tolerate component failures or environmental loss.

Recoverability

A reliability sub-characteristic describing the capacity to restore a broken system and data back to full service.

Usability

A software characteristic describing the extent to which the software can be understood and used with ease.

Understandability

A usability sub-characteristic determining the simplicity with which the system functions and mental models can be interpreted.

Learnability

A usability sub-characteristic concerning the ease with which diverse users learn application features.

Operability

A usability sub-characteristic measuring how conveniently an operator can control and manage the software in context.

Efficiency

A software characteristic describing the ability to use available system resources effectively and efficiently.

Time Behavior

An efficiency sub-characteristic characterizing transaction processing rates and reaction times.

Resource Behavior

An efficiency sub-characteristic characterizing the utilization of system resources like CPU, memory, disk, and network.

Maintainability

A software characteristic describing the ease with which modifications can be made to improve performance or fix errors.

Analyzability

A maintainability sub-characteristic characterizing the ability to determine the root cause of an issue.

Changeability

A maintainability sub-characteristic measuring the amount of system effort required to modify software.

Stability

A maintainability sub-characteristic characterizing the system's resilience against detrimental side effects when changes are made.

Testability

A maintainability sub-characteristic characterizing the effort needed to validate and test modifications.

Portability

A software characteristic describing the ease of transferring software across different platforms with minimal changes.

Adaptability

A portability sub-characteristic measuring software capability to adapt to new requirements or operating environments.

Installability

A portability sub-characteristic characterizing the effort required to install software in a target environment.

Conformance

A portability sub-characteristic describing conformity to standards impacting database or platform portability.

Replaceability

A portability sub-characteristic characterizing the ease of swapping a software component within a framework.

System Software

Programs that control core functions, hardware resources, memory, and multitasking, serving as an intermediary for applications.

Real-Time Software

Software that evaluates, analyzes, and commands real-world events as they take place within strict guaranteed response times.

Business Software

Software managing database transactions for commercial operations, such as payroll, accounting, and inventory.

Engineering and Scientific Software

Software executing precise calculations on complex statistical data in specialized domains like orbital tracking and astronomy.

Artificial Intelligence (AI) Software

Software capable of rational behavior that simulates logic, problem-solving, assessment, and knowledge representation.

Web-Based Software

Software acting as an interface between the user and the Internet, utilizing hyperlinked media and web browsers.

Personal Computer (PC) Software

Versatile software built for formal and personal use across everyday office, education, and home settings.

Corrective Maintenance

Software maintenance focused on repairing day-to-day faults, logic errors, and defects, accounting for 20% of maintenance activity.

Design Bugs

Defects introduced when software modifications are incomplete, incorrect, or based on misunderstood requirements.

Logical Bugs

Defects caused by wrong logic flow, invalid data tests, or incorrect algorithm implementations.

Coding Bugs

Programming mistakes that cause an executable module to produce unexpected and incorrect output.

Adaptive Maintenance

Modifications performed to adapt the system to changes in its operating environment, hardware, or business policies.

Perfective Maintenance

Enhancements based on user feedback to add new features or remove obsolete elements, accounting for 50-55% of maintenance.

Preventive Maintenance

Proactive changes such as code restructuring and updating documentation to improve maintainability and avoid deterioration.