Introduction to pub/sub pattern

Just as message queuing, pub-sub (publish-subscribe) pattern moves information from producer to a consumer. However the major difference here is this pattern allows multiple consumers to receive each message in a topic. It ensures that the consumer receives messages in a topic in exact same order in which it was received in the messaging system. This pattern can be better understood by taking a real life scenario. Consider a stock market. It is used by large number of people and applications, all of whom should be send messages real time and just the exact sequence of prices. There is a huge difference between a stock going up to down and stock going down to up. Lets see an example Apache Kafka is one of the shining solution when it comes to pub sub pattern. As per docs of Apache Kafka—Kafka is a distributed, partitioned, replicated commit log service. It provides the functionality of a messaging system, but with a unique design.

Kafka is a streaming platform...