Learn to build web apps that are reliable, fast, and engaging, offering an experience similar to native apps.
Progressive Web Apps (PWAs) are web applications that use modern web capabilities to deliver an app-like experience to users. They represent a significant evolution in what a website can do. The core technologies behind PWAs are the Web App Manifest and Service Workers. The 'Web App Manifest' is a JSON file that provides metadata about your application, such as its name, icons, and theme colors. This allows users to 'install' the web app to their home screen on mobile or desktop. 'Service Workers' are the real powerhouse. A service worker is a script that your browser runs in the background, separate from a web page. It acts as a programmable network proxy, allowing you to intercept and handle network requests. This capability is key to providing offline functionality. You can cache your application's shell (the core HTML, CSS, and JS) and even its data, so that it loads instantly and reliably, even on flaky networks or when completely offline. PWAs can also enable features like push notifications, further bridging the gap between web and native applications.