What is Verification and Validation?
Verification is verifying if we are building the right product? Does it conform to the specification? Validation is checking if we are building the product, right? Does it meet with the user expectation?
What is Test Strategy and Test Plan?
Test Strategy is a static document that consists of the approach for testing. It has generic details like which module can be tested and which test technique can be followed.
Test plan is a document that consists of all the activities to be performed in a certain testing project. Test Plan consists of the specific details like- What part of project has to be tested (Scope, Objective & Features to be tested), How can it be performed (Environment), Who can perform what? (Resources & Responsibilities), When can we stop the testing (Exit criteria) etc. It is dynamic document and the changes can be reflected while they are made.