JavaScript is the programming language that brings websites to life — it handles everything that moves, responds, or updates without reloading the page.
It was created in 1995 by Brendan Eich during his time at Netscape, and — fun fact — he built the first version in just 10 days. Originally meant to add basic interactivity to websites, JavaScript quickly became one of the most important languages on the internet. It runs directly in your browser and lets developers build dynamic, responsive, and real-time experiences — from drop-down menus to live chats, animations, online games, and even complex apps like Google Docs or Figma.
What makes JavaScript so essential?
It’s everywhere. Alongside HTML and CSS, JavaScript is one of the core technologies of the web. If you click a button and a modal pops up, or a shopping cart updates without refreshing — that’s JavaScript doing its thing. Over time, it’s expanded beyond browsers: thanks to tools like Node.js, JavaScript now powers backend servers, mobile apps (like with React Native), and even IoT devices.
It’s also the backbone of most modern frontend frameworks — React, Vue, Angular — all of which are written in or rely on JavaScript. Learning it opens doors to a huge ecosystem, and it’s often the first language taught in web development.
Want to dig deeper? Start here: JavaScript on MDN Web Docs
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