As websites become more interactive, with many moving parts that update based on user actions and data, writing raw JavaScript to manually track and update every piece of the DOM becomes hard to manage and error-prone. Front-end frameworks and libraries, most notably React, maintained by Meta, solve this by letting developers describe what the page should look like for a given state of data, and letting the framework handle efficiently updating the actual DOM when that data changes, using reusable pieces called components. Learning HTML, CSS, and JavaScript fundamentals first, as this course does, is the right order: frameworks like React are built on top of JavaScript and assume you already understand variables, functions, and DOM concepts, so skipping ahead to a framework before the fundamentals usually causes more confusion, not less.