DOM Manipulation

DOM Manipulation is the process of using JavaScript to interact with the Document Object Model (DOM), which is the browser's tree-like representation of an HTML document. When a web page is loaded, the browser creates this model, and every HTML element becomes a 'node' in this tree. JavaScript provides a powerful API to traverse and modify this tree, allowing you to create dynamic and interactive web pages. The first step is always selecting the element(s) you want to work with. You can use methods like `document.getElementById()`, `document.getElementsByClassName()`, `document.getElementsByTagName()`, and the more versatile `document.querySelector()` and `document.querySelectorAll()` which use CSS-style selectors. Once you have a reference to an element, you can change its content using properties like `.textContent` or `.innerHTML`. You can modify its style by accessing the `.style` property (e.g., `element.style.color = 'red'`). You can also change an element's attributes using `.setAttribute()` and `.getAttribute()`. Beyond just changing existing elements, you can create entirely new elements with `document.createElement()`, add content to them, and then insert them into the DOM using methods like `.appendChild()`, `.prepend()`, or `.insertBefore()`. Similarly, you can remove elements from the DOM with `.remove()`. Mastering DOM manipulation is a fundamental skill for any frontend developer, as it's the basis for how modern frameworks like React and Vue update the user interface.