A distributed event-streaming platform, the dominant open-source backbone for high-throughput async messaging and CDC.
Apache Kafka is a distributed, partitioned, replicated commit log designed for high-throughput event streaming. Producers append events to topics, consumers read at their own pace, partitions allow horizontal scaling, and replication provides durability. Kafka has become the dominant async backbone for everything from change-data-capture (CDC) to real-time analytics to event-driven microservice integration. Confluent, AWS MSK, and Azure Event Hubs offer managed equivalents.
Kafka decouples producers from consumers, which is the single most important property of a system that needs to scale teams as well as load. Producers don't know who consumes; consumers can replay history; broken consumers don't take down producers. The operational cost (clusters, ZooKeeper or KRaft, partition rebalancing) is real, but for most large systems the alternative is not 'simpler' but 'tightly coupled and fragile.'
See the part of the platform that handles kafka in production.