DOM: How JavaScript Reads and Changes Web Page Elements

The Document Object Model (DOM) is a programming interface that lets JavaScript access and modify HTML elements, their content, styles, and attributes. A simple example shows JavaScript selecting a heading by its ID and replacing its text from "Hello World" to "welcome". The article outlines core selection methods, including getElementById, getElementsByClassName, getElementsByTagName, querySelector, and querySelectorAll. It also covers changing HTML content and CSS styles through the DOM, along with handling user events such as button clicks.