System Development Life Cycle

A feasibility study is conducted to determine if creating a new or improved system is a viable solution.

Every activity that happens after the deployment of the software's life: changes, correction, additions, software moving to a different computing platform and more. All are a part of the maintenance phase. This is often the longest of the stages.

In systems design, the design functions and operations are described in detail, including screen layouts, business rules, process diagrams and other documentation. The output of this stage will describe the new system as a collection of modules or subsystems.

The key characteristic of a spiral model is risk management at regular stages in the development cycle. This model combines some key aspects of the waterfall model and rapid prototyping methodologies.

At the optimising level, the process management includes deliberate process optimisation/improvement.

An SRS should be unambiguous. Every requirement stated should have one and only one interpretation.

Constructive Cost Model (COCOMO) is an algorithmic software cost estimation model developed by Barry W. Boehm. The model uses a basic regression formula with parameters that are derived from historical project data and current as well as future project characteristics.

Validation is the process of evaluating software during or at the end of the development process to determine whether it satisfies specified requirements.

PERT stands for Program Evaluation Review Technique. A PERT chart is a project management tool that is used to schedule, organise, and coordinate tasks within a project.

Functional cohesion is when parts of a module are grouped because they all contribute to a single well-defined task of the module. It is the most desirable type of cohesion.

Content coupling (also known as pathological coupling) is when one module modifies or relies on the internal workings of another module.

White box testing tests internal structures or workings of a program. In white box testing, an internal perspective of the system as well as programming skills are used to design test cases. The tester chooses inputs to exercise paths through the code and determine the appropriate outputs.

A debugger or debugging tool is a computer program that is used to test and debug other programs. Assertions provide a very powerful tool in debugging.

A test script is a procedure or programing code that replicates user actions.

Compatibility testing, part of software non-functional tests, is testing conducted on the application to evaluate the application's compatibility with the computing environment.