List the components of an Apache Kafka cluster.

Main components of an Apache Kafka cluster:

• Broker — a server that stores and transmits messages.
• Topic — a logical category or channel where messages are published.
• Partition — a division of a topic for parallel processing and scaling.
• Producer — a client that publishes messages to topics.
• Consumer — a client that reads messages from topics.
• Consumer Group — a group of consumers that jointly read data from a topic, distributing the load.
• Zookeeper (in the classic architecture) — a service for coordination and management of the cluster (in newer Kafka versions, it may use its own mechanism).

These components provide a reliable, scalable, and fault-tolerant messaging system.