V-Model
The V-Model is a software development and testing methodology that emphasizes a structured, sequential approach where each development phase has a corresponding testing phase, forming a V-shaped diagram. It is an extension of the waterfall model, with verification and validation activities integrated throughout the lifecycle to ensure quality and reduce defects. The left side of the V represents development phases (e.g., requirements, design), while the right side maps to testing phases (e.g., unit testing, system testing).
Developers should use the V-Model in projects with well-defined, stable requirements and a need for rigorous testing, such as in safety-critical systems (e.g., aerospace, medical devices) or regulated industries where documentation and traceability are essential. It helps catch defects early by aligning testing activities with development stages, reducing rework costs and improving reliability, but is less suitable for agile or rapidly changing environments due to its inflexibility.