V-Model

The V-model is basically a visual way of mapping out a development lifecycle. It is used to build strict, well-defined development and project management processes. It lays out the key steps a team needs to take alongside the matching deliverable for each step, especially in fields where systems need to be properly validated before going live. In short, it spells out exactly what needs to be done and what result should come out of each stage of development.

How Testing Runs Parallel to Development

In the V-model, every development phase has a corresponding testing phase right next to it. For example, while requirements are being defined, the team is also planning acceptance tests for those exact requirements. This pairing continues all the way through, so testing is built into the process rather than left until the end.

Advantages and Disadvantages

Because testing happens alongside development, bugs get caught much earlier compared to Waterfall. This usually leads to a more reliable final product. However, just like Waterfall, the V-model is rigid. It does not handle changing requirements well, and going back to fix something in an earlier phase is still costly.

When to Use V-Model

The V-model fits projects where requirements are well defined and unlikely to shift, but where quality and thorough testing are critical, such as in medical, banking, or safety related software.