Apache Kafka is not a traditional message queue. Kafka is a distributed messaging system that includes components of both a message queue and a publish-subscribe model.  

Kafka improves on the deficit of each of those traditional approaches allowing it to provide fault tolerant, high throughput stream processing. 

Traditional shared message queues are limited because messages are removed from the queue after a single consumer reads it.  This approach isn’t compatible with building highly scalable systems.

Kafka uses consumer groups and broker retention to combine the two models of the message queue and publish-subscribe to create a more scalable and reliable approach to message processing. 

You can learn more about how Kafka using consumer groups for scaling event streaming here.