What is the role of topics in Kafka architecture and why are they used?

In Apache Kafka, topics are logical channels through which messages are exchanged between producers and consumers.

Role of topics:

• Data organization: Topics group messages by categories or data types, simplifying processing.
• Stream partitioning: Each topic can have multiple partitions, allowing for scalable processing and parallelism.
• Order guarantee: Within a single partition, message order is preserved, which is important for sequential processing.

Why use topics:

• They allow separation of different data types and services.
• They provide scalability and fault tolerance.
• They simplify subscription and message filtering for consumers.

Example: If you have a logging system, you can create a "logs" topic, where producers send messages, and various services (consumers) read them for analysis, monitoring, and storage.