Verification is a set of activities carried out to see 
whether we are we building the system right.

Validation is a set of activities carried out to check 
whether we are we building the right system.

Verification: Test execution to insure all functionalities 
stated in RA are delivered.

Validation: Test execution to insure all functionalities 
delivered as stated in RA are working as per requirement

Verification typically involves reviews and meetings,to 
evaluate the 
requirements,specifications,documents,code,plans.This can 
be done with the check lists,walk throughs,inspections and 
meetings.

Validation typically involves the actual testing process
the validation takes place after the verification is done.

Verification:  It is a process confirming that software 
meets its specification document. It basically involves 
walkthroughs, review and inspection. QA team members define 
the process as per the specification.

Validation:   It is a process confirming that software 
meets its user requirements. It basically involves testing. 
Validation technique done after verification process. QC 
team like testers they r going to implementing the process 
defined by QA team.

Verification is QA activity which ensures that the software 
product is designed to deliver all the functionality 
whatever mentioned in the requirement specification 
document. Reviews, walkthroughs and inspections are its 
techniques. It is a preventive phase.

Validation ensures that whatever mentioned in the 
requirement specification document should be the intended 
behavior of the software. Validation is actual testing. It 
is a corrective phase and is QC activity. 

Vimal (Test Engg.)

Validation is done after verification