Verification and validation in testing

There is more than one interpretation of what validation is and what verification is, however, all of them are not written in the simplest terms and to understand the essence of both is a task worthy of a prize.

Let us consider these two terms from a slightly different angle to show an understandable example.

Verification and validation

So, verification and validation on the example of a pirate ship:

So, verification:

Is there a hull? –  Yes, there is.

Is there a mast? – Yes.

Funny Roger? – No.

What about the wheel? – No, there isn’t a wheel.

and a sail? – N- Oh, this one actually is there.

...

All of them? – No, just one.

Validation:

Does the ship even float? Does the ship stay afloat?

Then all of the above, but in a more technical text:

Verification is a confirmation that certain requirements have been met.

Validation is a verification that the product meets users' expectations and needs.

Putting the terms above in practice, let us suppose there is a site/application or something else.

In order to enter, we need to register/log in.

So, we have a form with fields that need to be filled in:

So let us conduct a verification first:

We check the fields. All fields must meet the specification. Their availability is determined by designers who create layouts. The necessary information is entered in the terms of reference (TOR), and in the absence of such information, it is desirable to have access to mockups. 

Conducting the verification, we first keep in mind that all fields are working, it is possible to enter various data in them according to the names.

Then validation:

As part of the validation, the information entered in the fields and its compliance with the specification are checked:

Let's look at another, more detailed example based on Facebook login/authorization:

Suppose, there is a specification and the presence of fields on the landing page corresponds to it. Based on this, the verification was successful.

Next, we will conduct validation. In order not to delay, the invalid data is entered in the fields of the registration form:

As you can see from the screenshot, the entered data did not pass validation and we were not allowed to continue, which was necessary to check.

Short conclusions:

• during verification, the presence of something is checked;
• during validation, we check the operability of this «something».