The validator checks the mark up validity of Web documents in HTML, XHTML, SMIL, Math ML, etc. If you wish to validate specific content such as RSS/Atom feeds or CSS style sheets or to find broken links, there are other validators and tools available on the web page. In software project management, software testing, and software engineering, Verification and Validation (V And V) is the process of checking that a software system meets specifications and that it fulfils its intended purpose. It is normally part of the software testing process of a project. In pharmaceutical industry, verification involves testing the suitability of well established procedures or (compendial) methods, whereas validation varies from Cross validation, Empirical validation, periodic partial validation, internal/external validation, competence validation by nature, and Cleaning validation, Process validation, Equipment validation, or Documentation validation by tasks. Verification ensures that the final product satisfies or matches the original design (low level checking) , you built the product right. This is done through static testing.

Validation checks that the product design satisfies or fits the intended usage (highlevel checking) , you built the right product. This is done through dynamic testing and other forms of review.

According to the Capability Maturity Model , Validation The process of evaluating software during or at the end of the development process to determine whether it satisfies specified requirements. [IEEESTD610] Verification 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.

In other words, verification is ensuring that the product has been built according to the requirements and design specifications, while validation ensures that the product actually meets the user's needs, and that the specifications were correct in the first place. Verification ensures that you built it right. Validation confirms that the product, as provided, will fulfill its intended use. Validation ensures that you built the right thing.

Now there are sites that still do rank well even though the html code has many errors. This is because most of the current major browsers are still very forgiving of html mistakes, however future browsers will become more html compliant as the Internet advances. Sites that have not bothered with html code validation will then fall by the wayside or take time and money to be corrected. That's why you should take the necessary steps NOW to make sure that the code on your web site is validated.

This is the process that analyzes an HTML document in comparison to standard HTML rules, identifying errors and nonstandard codes. Web pages are rendered using HTML (Hyper Text Markup Language). As with any language there are rules and standards that should be followed. For example the HTML 4.01 Specification (rules and standards) are available. You can check the html validation of your web page by entering your url at: http://validator.w3.org/