In web development, key technologies include JavaScript and TypeScript for dynamic content and scalable applications, React for building reusable user interfaces, and Next.js for server-side rendering to enhance performance and SEO. React Testing with tools like Jest ensures component reliability. Ruby & Ruby on Rails provide a dynamic language and framework for rapid application development. Node.js is essential for server-side scripting, making web applications efficient, while NestJS, leveraging TypeScript, offers a framework for constructing scalable server-side applications. These technologies form the core toolkit for modern web development, covering both client and server-side needs.