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Progressive Web Apps

Web apps that install, work offline, and feel native.

4 min read · intro · beat Silver to climb

The idea

A Progressive Web App (PWA) is a website that uses modern browser features to behave like an installed app. It can launch from the home screen, run offline, and send notifications, all from a single codebase.

The core pieces

  • A web app manifest, a JSON file describing the name, icons, and display mode.
  • A service worker that caches assets so the app loads offline.
  • A secure HTTPS origin, which both features require.

What users get

When these conditions are met, browsers offer an install prompt. The installed app opens in its own window without browser chrome, and cached assets make it start fast even on flaky networks.

Why teams choose it

A PWA reaches users across devices without app store builds. Updates ship the moment you deploy, since the app is still the web under the hood.

Key idea

A PWA adds a manifest and a service worker over HTTPS to make a website installable, offline capable, and app like.

Check yourself

Answer to earn rating on the learn ladder.

1. Which file makes a PWA installable by describing its icons and name?

2. What enables a PWA to load while offline?