What is a Kafka topic and how is it different from a traditional queue?

A Kafka topic is how events are organized and durably stored; the docs liken it to a folder in a filesystem with the events as the files. A topic is split into partitions, and a new event is appended to one of them. Topics are always multi-producer and multi-subscriber, and events are not deleted after consumption: they can be read as often as needed by as many consumers or consumer groups as you want, each tracking its own position. How long events are kept is set by a per-topic retention setting (time or size), not by whether they were read. Ordering is guaranteed within a partition, not across the whole topic. This differs from a queue that hands each message to one consumer and removes it once it is consumed.

Expected key concepts: topic, folder, partitions, multi-subscriber, consumer groups, not deleted after consumption, retention, ordering, durably stored