Pusher Presence channels are a feature within Pusher Channels that enable developers to create a live "who's online" feature by providing users with a list of channel occupants and notifying them when new users subscribe or unsubscribe. Built on top of private channels for added security, Presence channels are suitable for applications like chat apps, online games, and collaborative tools where knowing the online status of users is crucial. They require authorization and use a specific prefix (presence-) to operate, allowing users to see who has joined or left, who is online, and the number of members in the channel. Presence channels are ideal for small groups of subscribers, and the infrastructure simplifies the process by managing long-lived WebSocket connections and broadcasting events when presence states change. Although they are limited to channels with fewer than 100 members, developers can leverage other Pusher capabilities and webhooks for larger groups. The Pusher platform offers various tools and documentation to facilitate the integration of Presence channels into applications, ensuring a seamless and efficient real-time user experience.