Validation and verification  

What is the difference between validation and verification? 

Validation answers the question of whether something is most likely to work in the future. In technical terms: it is the confirmation of a claim that the requirements for a specific intended use or application are met. This confirmation must be supported by objective evidence. 

Verification answers the question of whether something already works in the present. In technical terms: this is the confirmation of a claim that specified requirements are met. This confirmation must be supported by objective evidence.