Consumer Group
A set of consumers sharing the same group.id that split a topic's partitions among themselves.
Within a Consumer Group, each partition of a topic is assigned to exactly one consumer in the group at any given time — which distributes work, similar to a queue. Different Consumer Groups, however, are completely independent of each other: each group keeps its own set of offsets and can read the same topic without interfering with the others. It's this combination that lets Kafka both distribute work and share the same data with multiple systems.
Related chapters