# shwcs.net Web Platform Capabilities — Open Knowledge Format bundle

A knowledge base of modern web platform capabilities, one concept per capability, grouped by category. Each concept describes what the capability does, which browser engines support it, its runtime requirements, and where to try it live.

## 📱 PWA & Install

- [Install Prompt](/okf/pwa-install/install-prompt.md) — Prompt visitors to install this site as an app.
- [Web App Manifest](/okf/pwa-install/web-app-manifest.md) — Metadata that makes a site installable: name, icons, display mode.
- [Service Worker](/okf/pwa-install/service-worker.md) — Programmable network proxy enabling offline and background features.
- [Offline Support](/okf/pwa-install/offline-ready.md) — Service worker + Cache API together make this site work offline.
- [App Badging](/okf/pwa-install/badging.md) — Show a badge count on the installed app icon.
- [App Shortcuts](/okf/pwa-install/app-shortcuts.md) — Jump-list entries on the installed app icon (manifest `shortcuts`). Runtime-probed via install-prompt proxy.
- [Share Target](/okf/pwa-install/share-target.md) — Receive shares from other apps into this PWA (manifest `share_target`). Runtime-probed via install-prompt proxy.
- [File Handling](/okf/pwa-install/file-handlers.md) — Register the installed app as a handler for file types.
- [Protocol Handling](/okf/pwa-install/protocol-handlers.md) — Register as handler for custom URL schemes (`web+…`).
- [Window Controls Overlay](/okf/pwa-install/window-controls-overlay.md) — Draw into the title-bar area of the installed desktop app.

## 💾 Storage & Files

- [Origin Private File System](/okf/storage-files/opfs.md) — A private, origin-scoped filesystem with fast synchronous access from workers.
- [IndexedDB](/okf/storage-files/indexeddb.md) — Transactional object database for large structured data.
- [Cache Storage](/okf/storage-files/cache-api.md) — Store request/response pairs — the backbone of offline apps.
- [Storage Quota & Persistence](/okf/storage-files/storage-quota.md) — Inspect how much you can store and request persistent (non-evictable) storage.
- [File System Access](/okf/storage-files/file-system-access.md) — Open and save real files on the user's disk via native pickers.
- [Compression Streams](/okf/storage-files/compression-streams.md) — Gzip/deflate compression and decompression as native streams.

## 🔌 Device Access

- [Web Bluetooth](/okf/device-access/web-bluetooth.md) — Connect to Bluetooth LE devices and read/write GATT characteristics.
- [WebUSB](/okf/device-access/webusb.md) — Talk to USB devices directly from the page.
- [Web Serial](/okf/device-access/web-serial.md) — Read/write serial ports — Arduinos, printers, industrial gear.
- [WebHID](/okf/device-access/webhid.md) — Communicate with human-interface devices beyond keyboard/mouse.
- [Web NFC](/okf/device-access/web-nfc.md) — Read and write NFC tags (Android only).
- [Web MIDI](/okf/device-access/web-midi.md) — Connect MIDI instruments and controllers.
- [Gamepad](/okf/device-access/gamepad.md) — Read connected game controllers: buttons, axes, rumble.
- [Keyboard Lock](/okf/device-access/keyboard-lock.md) — Capture system keys (Esc, Alt-Tab) in fullscreen.
- [Pointer Lock](/okf/device-access/pointer-lock.md) — Unlimited relative mouse movement for games and 3D.

## 🧭 Sensors & Location

- [Geolocation](/okf/sensors-location/geolocation.md) — Current position and continuous location watching.
- [Device Orientation & Motion](/okf/sensors-location/device-orientation.md) — Tilt, rotation and acceleration events from the device.
- [Accelerometer](/okf/sensors-location/accelerometer.md) — Generic Sensor API accelerometer readings.
- [Gyroscope](/okf/sensors-location/gyroscope.md) — Angular velocity around three axes.
- [Magnetometer](/okf/sensors-location/magnetometer.md) — Magnetic field readings — a compass.
- [Ambient Light Sensor](/okf/sensors-location/ambient-light.md) — Environmental light level in lux.
- [Compute Pressure](/okf/sensors-location/compute-pressure.md) — Observe CPU pressure to adapt workloads.

## 🎥 Media & Capture

- [Camera & Microphone](/okf/media-capture/get-user-media.md) — Capture live camera and microphone streams.
- [Screen Capture](/okf/media-capture/screen-capture.md) — Capture a tab, window or the whole screen.
- [MediaRecorder](/okf/media-capture/media-recorder.md) — Record audio/video streams to files.
- [Picture-in-Picture](/okf/media-capture/picture-in-picture.md) — Pop videos out into a floating always-on-top window.
- [Document Picture-in-Picture](/okf/media-capture/document-pip.md) — A floating window with arbitrary HTML content.
- [Media Session](/okf/media-capture/media-session.md) — Integrate with OS media controls and lock-screen UI.
- [Barcode Detection](/okf/media-capture/barcode-detection.md) — Detect QR codes and barcodes in images or camera frames.
- [Speech Synthesis](/okf/media-capture/speech-synthesis.md) — Text-to-speech with system voices.
- [Speech Recognition](/okf/media-capture/speech-recognition.md) — Speech-to-text from the microphone.
- [Web Audio](/okf/media-capture/web-audio.md) — Synthesize, process and analyze audio in real time.
- [WebCodecs](/okf/media-capture/webcodecs.md) — Low-level access to hardware video/audio encoders and decoders.

## 🎮 Graphics & Compute

- [WebGL 2](/okf/graphics-compute/webgl.md) — Hardware-accelerated 3D rendering.
- [WebGPU](/okf/graphics-compute/webgpu.md) — Modern GPU API for rendering and compute shaders.
- [OffscreenCanvas](/okf/graphics-compute/offscreen-canvas.md) — Render canvases from workers, off the main thread.
- [WebAssembly](/okf/graphics-compute/webassembly.md) — Near-native execution of compiled code.
- [Web Workers](/okf/graphics-compute/web-workers.md) — Run scripts on background threads.
- [SharedArrayBuffer & Cross-Origin Isolation](/okf/graphics-compute/shared-array-buffer.md) — Shared memory between threads — requires COOP/COEP headers.

## 📡 Communication & Background

- [WebRTC](/okf/communication-background/webrtc.md) — Peer-to-peer audio, video and data channels.
- [WebSocket](/okf/communication-background/websocket.md) — Bidirectional persistent connection to a server.
- [WebTransport](/okf/communication-background/webtransport.md) — Low-latency client-server messaging over HTTP/3.
- [Notifications](/okf/communication-background/notifications.md) — System notifications from the page.
- [Push Messages](/okf/communication-background/push.md) — Server-sent push messages, even when the page is closed.
- [Background Sync](/okf/communication-background/background-sync.md) — Defer work until connectivity returns.
- [Background Fetch](/okf/communication-background/background-fetch.md) — Large downloads/uploads that outlive the page.
- [Periodic Background Sync](/okf/communication-background/periodic-sync.md) — Periodically refresh content in the background.
- [BroadcastChannel](/okf/communication-background/broadcast-channel.md) — Message all same-origin tabs and workers.

## 🖥️ OS Integration

- [Async Clipboard](/okf/os-integration/async-clipboard.md) — Read and write text and images to the system clipboard.
- [Web Share](/okf/os-integration/web-share.md) — Open the native share sheet with text, links or files.
- [Screen Wake Lock](/okf/os-integration/wake-lock.md) — Keep the screen awake while the page is visible.
- [Vibration](/okf/os-integration/vibration.md) — Trigger haptic vibration patterns (mobile).
- [Battery Status](/okf/os-integration/battery.md) — Charge level and charging state.
- [Network Information](/okf/os-integration/network-info.md) — Connection type, downlink estimate, save-data hint.
- [Idle Detection](/okf/os-integration/idle-detection.md) — Detect when the user goes idle or locks the screen.
- [Fullscreen](/okf/os-integration/fullscreen.md) — Take any element fullscreen.
- [Screen Orientation](/okf/os-integration/screen-orientation.md) — Read — and on mobile, lock — the screen orientation.
- [EyeDropper](/okf/os-integration/eyedropper.md) — Pick a color from anywhere on the screen.
- [Local Font Access](/okf/os-integration/local-fonts.md) — Enumerate fonts installed on the system.
- [Window Management](/okf/os-integration/window-management.md) — Multi-screen awareness and cross-screen window placement.
- [Contact Picker](/okf/os-integration/contact-picker.md) — Let the user share contacts from their address book (mobile).

## 🔐 Identity & Payments

- [WebAuthn / Passkeys](/okf/identity-payments/webauthn.md) — Passwordless sign-in with platform authenticators and passkeys.
- [Credential Management](/okf/identity-payments/credential-management.md) — Store and retrieve credentials via the browser.
- [Payment Request](/okf/identity-payments/payment-request.md) — Native payment sheets — Apple Pay, Google Pay and cards.
- [Federated Credential Management](/okf/identity-payments/fedcm.md) — Privacy-preserving federated login without third-party cookies.

## ✨ Modern UI

- [View Transitions](/okf/modern-ui/view-transitions.md) — Animated transitions between DOM states and pages.
- [Popover](/okf/modern-ui/popover.md) — Built-in top-layer popovers with light dismiss — no JS library.
- [Dialog Element](/okf/modern-ui/dialog.md) — Native modal dialogs with focus trapping and backdrop.
- [Scroll-Driven Animations](/okf/modern-ui/scroll-driven-animations.md) — Animations driven by scroll position, off the main thread.
- [Speculation Rules](/okf/modern-ui/speculation-rules.md) — Prerender likely next pages for instant navigation.