Validation

Validation is the process of confirming that a software system meets the real-world needs of its intended users and fulfills the agreed business requirements in its operational environment.

Validation asks the question "are we building the right product?" — distinct from verification, which asks whether the product was built correctly against specifications. Where verification checks internal documents and designs, validation tests the system against actual user needs and acceptance criteria, typically in conditions that reflect real operational use.

In the SDLC, validation activities cluster toward the later stages: system testing, user acceptance testing (UAT), and operational readiness reviews. Testers evaluate whether the software behaves as end users expect, whether performance benchmarks are met under realistic load, and whether security posture satisfies agreed thresholds. Input data checks and database constraint testing can surface gaps between what the system accepts and what the business actually processes.

Validation encompasses several recognized types. Alpha and beta testing expose the product to controlled or real user groups before release. Acceptance testing, driven by user acceptance criteria, is the formal gate that determines whether a system is fit for purpose. Usability testing scenarios and regression test suites may both feed into a validation cycle, depending on scope and contractual obligations.

• en.wikipedia.org — Software verification and validation