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Explain three important components of Dynamic HTML authoring - Positioning, Style modifications and Event handling1. Positioning : Is some what where we need the object to be placed in the graphical view i:e on screen. If we talk in DHTML sense then we have two types of positioning: Relative and Absolute.
2. Relative Positioning : Relative positioning is the same as the current HTML3 layout and is best reserved for situations where you want to be sure that the content will revert to this default inside a document that also uses absolute positioning.
3. Absolute Positioning : In DHTML absolute positioning means that the object will remain at the same position regardless of the condition of other elements and the size of the browser. In simple languages if an object/image is absolutely positioned (STYLE="position: absolute;"), with an offset of 150 pixels to the right and 250 pixels down from the left-hand corner of the browser screen then it will avail this position what ever the circumstances may be.
4. Style Modifications : Style modification indicates the changes in the presentation or the view part that are being made in web page. This part comes under Cascading Style Sheet where the user style his web page by using the attributes and the tags that are pre-defined in CSS.
5. Event Handling : As explained earlier Events is the beating heart of any JavaScript application. For handling event in DHTML we attach event handler to HTML elements. The event handler waits until a certain event, for instance a click on a link, takes place. When it happens it handles the event by executing some JavaScript code that has been defined by us. After it has executed the code the event handler comes to its initial state and waits for the user to fire any event. Hence to handle events in DHTML we need to register an event handler.
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