Which applications does DOM API help to communicate with each other?

In What Is an API, and What Are Web APIs? and What Is the DOM, and How Do You Access Elements?, the teacher said

APIs establish a set of rules and protocols that allow software applications to communicate with each other and exchange data efficiently.

DOM stands for Document Object Model. It’s a programming interface that lets us interact with HTML documents.

However, I’m still confused about which applications DOM API helps to communicate. Is the description below correct?

For instance, A weather app uses an API to obtain local weather data from a weather website.
A HTML document (webpage) that uses DOM methods in JavaScript files to manipulate page elements is equivalent to a weather app; the DOM methods in JavaScript files play the role of API; and the browser is equivalent to a weather website that provides data - only here, the browser changes the DOM structure.

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