The JavaScript is the most popular and powerful language for writing Client-Side scripts. Using JavaScript with CSS and HTML allows easy way to create powerful and interactive Web pages. Using JavaScript with CSS and HTML frequently named as Dynamic HTML. The JavaScript gives to you practically complete control under browser's behavior. The given examples shows: how to work with layers, how to handle events from the mouse and keyboard, how to use filters, how to control a state of HTML tags, and many other things. The additional information and documentation you can find here. Enjoy!