Verification refers to the set of activities that ensure that software correctly implements a specific function.Verification is done against the design. It verifies that the software being developed implements all the functionality specified in the design document.

Verification ensures that the system (software, hardware, documentation, and personnel) complies with an organization’s standards and processes, relying on review or non-executable methods.

It answers the questions like: Am I building the product right?

Am I accessing the data right (in the right place; in the right way).

It is a Low level activity

Performed during development on key artifacts, like walkthroughs, reviews and inspections, mentor feedback, training, checklists and standards.

Demonstration of consistency, completeness, and correctness of the software at each stage and between each stage of the development life cycle.

Advantages of Software Verification :

1) Verification helps in lowering down the count of the defect in the later stages of development.

2) Verifying the product at the starting phase of the development will help in understanding the product in a better way.

3) It reduces the chances of failures in the software application or product.

4) It helps in building the product as per the customer specifications and needs.

Validation: "Are we building the right product?"

Validation refers to a different set of activities that ensure that the software that has been built is traceable to customer requirements. Validation is done against the SRS(Software Requirement Specification). It verifies that the software being developed implements all the requirements specified in the SRS document.

Validation physically ensures that the system operates according to a plan by executing the system functions through a series of tests that can be observed and evaluated.

Validation is the process of comparing a product to its high level requirements. Thus using a validation method to determine if a system does what the requirements said it should is validation. The same methods used for verification can also be used for validation.

Advantages of Software Validation:-

1) The defects missed during the validation process can be detected during the verification process.

2) The validation is performed during the testing such as stress testing, compatibility testing, system testing, feature testing, etc.

3) Validation assists in developing the right product according to the requirement of the customers.