Over the last few years there has been a remarkable increase in use of the World Wide Web (WWW) for a wide and variety of purposes. There was also a fast growth in its applications. On the one hand this led the Internet users to realize the importance and the benefits gained from a globally interconnected hypermedia system. Due to the increasing popularity of WWW, one can be very cautious in designing the website. Poor and careless web design leads to hardship to public utility and does not serve the purpose. The important quality attributes for web applications include reliability, availability, interoperability and security. Therefore methodologies for analyzing, constructing, understanding, testing and maintaining web applications will be essential to the IT industry. The quality assurance techniques for web applications generally focus on the prevention of web failure or the reduction of chances for such failures. The web failures are defined as the inability to obtain or deliver information such as documents or computational results requested by web users.