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We will list here the terms that are related to the Socket.IO ecosystem:


An Adapter is a server-side component which is responsible for:

  • storing the relationships between the Socket instances and the rooms
  • broadcasting events to all (or a subset of) clients

There are currently two official adapters:

The in-memory adapter can be extended to add support for other messaging systems, like RabbitMQ or Google Pub/Sub for example.

Please see the documentation here.


A Namespace is a concept that allows splitting the application logic on the server-side.

Please see the documentation here.


A Room is a server-side concept that allows broadcasting data to a subset of clients.

Please see the documentation here.


A Transport represents the low-level way of establishing a connection between the server and the client.

Please see the documentation here

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