Apache Kafka is an open-source stream-processing software platform developed by the Apache Software Foundation, written in Scala and Java. The project aims to provide a unified, high-throughput, low-latency platform for handling real-time data feeds.

In a nutshell, you say data to it and you can do something with that data. Here we will process data from Oracle through Kafka to big data.

So for example, you can have: Oracle → Kafka → Hadoop/Hbase