Progressive Web App (PWA) Vocabulary

Learn PWA vocabulary: manifest.json, installability, Add to Home Screen, offline mode, push notifications, and how to explain "the app works offline because".

Vocabulary Reference

manifest.json (Web App Manifest)
A JSON file linked from the HTML that provides metadata about the app: name, short_name, icons, start_url, display mode, and theme/background colours. Required for installability.
installability
The set of criteria (HTTPS, valid manifest, service worker with fetch handler) a PWA must meet before the browser will offer an install prompt.
Add to Home Screen (A2HS)
The user gesture (or browser-triggered prompt) that installs a PWA to the device home screen. In Chrome, this is gated by the beforeinstallprompt event.
offline mode
The ability of a PWA to load and function without a network connection, achieved by a service worker serving cached assets and data.
push notification
A message sent from a server to a PWA via the Push API and displayed by the service worker using the Notifications API, even when the app is not open.
"the app works offline because..."
A standard explanation phrase: "...the service worker intercepts fetch requests and serves cached responses when the network is unavailable."