Dynamic HTML or DHTML, is the one that through the use of JavaScript is modified as the user interacts with it. The term is in disuse since anything done with JavaScript such as AJAX, animations, sliders, carousels, form validation, etc., is considered and practically all websites have dynamic elements.
In addition, many of them have mobile application functionalities, being considered not as web pages, but as web applications or PWAs (Progressive Web Applications).
Importance of DHTML in SEO
In SEO, attention should be paid to how some functionality is implemented, as it will affect what the spider bot will see on the page, since it does not always execute JavaScript and does not perform user actions such as button clicks.
For example, it is important to study whether the contents displayed dynamically in pop-ups or tabs are relevant for positioning or not, and whether they appear hidden on the page or not, or whether the contents loaded with AJAX are indexable.
Difference between DHTML and dynamic page
The term DHTML should not be confused with dynamic page.Dynamic page: a dynamic page is the one generated by means of some server language, being able to be built in a different way based on the parameters it receives, as opposed to a static page, which is the one that does not use programming, so it is always the same.
The fundamental difference between DHTML and a dynamic page is that DHTML is dynamic or changes on the client and the dynamic page on the server.
Additional references
Understand basic SEO concepts in JavaScript
Google videos about Javascript SEO
