JavaScript integration enables dynamic functionality across web applications. Modern JavaScript frameworks like React, Vue, and Angular provide structured approaches to building interactive interfaces. These frameworks use component-based architectures for reusable, maintainable code.

Integrate JavaScript with backend APIs using Fetch API or libraries like Axios. Handle asynchronous operations with async/await syntax for clean, readable code. Implement client-side routing for single-page applications without full page reloads. Use state management solutions like Redux or Vuex for complex application state.

Consider server-side rendering (Next.js, Nuxt.js) for improved initial load performance and SEO. Implement progressive web app features for offline capability and app-like experiences. Use build tools like Webpack or Vite for optimized production bundles. Regularly update dependencies and follow security best practices.