I am not sure what DOM is. But based on my understanding through my lecture slides and online source.
By applying DOM approach, which allowing you to create/update/modify the certain HTML elements dymanically.
Am I correct?

Yes. It's the description of the structure and API (application programming interface) of a document. For details please see the w3 description.

The Document Object Model (DOM) is a programming API for HTML and XML documents. It defines the logical structure of documents and the way a document is accessed and manipulated.

commented: yet more cut and pasted content - are you unable to think for yourself or are you just here for the spamming? PS I already know the answer -3