Progressive Web Apps (PWA) — Roadmap Step & Resources

Service workers, offline support and installable web apps

Study resources

Progressive Web Apps (PWAs) (Article) — web.dev's official hub of guides for building installable, offline-capable web apps.
PWA Crash Course (Video) — Traversy Media's crash course on converting a web app into an installable PWA.
Offline and background operation (Article) — MDN's technical guide to caching assets and background operation using service workers.
Progressive Web Apps Tutorial for Beginners (Video) — Net Ninja covers service workers, app manifests, cache storage APIs, and offline fallback functionality.