Validation in simple terms means confirmation.

In context of software, it means evaluating the final software product to check whether it complies with the business requirements from the end users perspective. Our goal of Validation is to answer the fundamental question “Are we building the right product?”. Test execution is the validation activity by which a product is tested. It includes various types such as User Acceptance Testing (UAT), smoke testing, regression testing, functional testing, systems testing, feature testing, integration testing, load testing, compatibility testing, stress testing, etc.