JavaScript

JavaScript (JS) is the programming language of the web that makes web pages interactive. It runs in the browser (client-side) and since Node.js also on servers. JavaScript enables: DOM manipulation, event handling, asynchronous requests (AJAX/Fetch), animations, single-page applications (SPAs). Modern JS frameworks: React, Vue.js, Angular, Svelte. TypeScript extends JS with static typing. For SEO: JavaScript rendering can be problematic - Server-Side Rendering (SSR) or Static Site Generation (SSG) solves this. Frameworks like Next.js (React) and Nuxt (Vue) make SSR easy. JavaScript is also essential for web analytics (GA4, Tag Manager).