...Producers append records to partitions, brokers replicate them for durability, and consumer groups read them at their own pace while balancing work across instances. The commit/offset model and retention policies support patterns from real-time processing to event sourcing and audit trails. Exactly-once processing semantics, idempotent producers, and transactions help prevent duplicates across complex dataflows. Kafka Streams and Kafka Connect extend the core: Streams provides a library for stateful stream processing within applications, while Connect standardizes integration with external systems. ...