It represents the page so that programs can change the document structure style and content.
In the dom all html elements are defined as objects. The dom represents the document as nodes and objects. The document object model dom connects web pages to scripts or programming languages by representing the structure of a document such as the html representing a web page in memory.
The basic code is. The changes are called by a timer. The dom model is created as a tree of objects like this.
When the timer interval is small the animation looks continuous.