You go for a driving test. The instructor/officer, tests you for the various factors while you are driving. IN software, you run a software to test for the various capabilities/functions that it has/can perform successfully and repeatedly.
Again in the driving context... You get a driving licence which says it is valid till a cetain date, afdter which it becomes invalid, unless revalidated by the competent authority. Yet another example...no product/document is legal unless it is validated by the competent authority.
Thank you so very much for your clarification on my doubt but still i didn't get this point
" no product/document is legal unless it is validated by the competent authority"
can you please again clarify it ?
The process of evaluating software to determine whether the products of a given development phase satisfy the conditions imposed at the start of that phase.
Validation: The process of evaluating software during or at the end of the development process to determine whether it satisfies specified requirements. [IEEE-STD-610]
In other words, validation ensures that the product actually meets the user's needs, and that the specifications were correct in the first place, while verification is ensuring that the product has been built according to the requirements and design specifications. Validation ensures that ‘you built the right thing’. Verification ensures that ‘you built it right’. Validation confirms that the product, as provided, will fulfil its intended use.