JavaScript instructs the user to create exciting web pages that employ the power of JavaScript to provide functionality. It allows dynamic content to get executed in a webpage. It does not incorporate any HTML tags or rules. It is not a stand-alone language, but rather it is a scripting add-on to HTML. It is one of the basics of web designing technology of which any web developer should have a thorough knowledge and understanding. This book focuses on aiding the reader to incorporate all features of JavaScript to create an interactive web page. The book not only serves the academic learning, but also shall be a reference guide for practitioners.