Core concepts

playhtml gives you four primitives for moving state between readers. Once you can reach for the right one, everything else is just attribute names.

• Element data (defaultData / can-play) — persistent state scoped to a single DOM element. A toggle’s on/off, a draggable’s position, a shared count. Survives reload. See data essentials for shape, updates, and cleanup.
• Page data (playhtml.createPageData) — persistent state keyed by a name, not tied to any element. A page-level counter, a shared prompt, an open vote. See page-level data.
• Presence (playhtml.presence / cursor awareness) — ephemeral per-user state: “who’s online”, “who’s typing”, “where’s my cursor”. Disappears when users disconnect. See presence and cursors.
• Events (playhtml.dispatchPlayEvent) — one-off broadcasts with no persisted state. Confetti, chimes, notifications. See events.

Not sure which one you want? The decision table on data essentials lays out the tradeoffs side by side.