This document provides an overview of Apache Kafka and Twitter Storm for event processing. It begins with an introduction to Kafka, describing it as a distributed publish-subscribe messaging system designed for processing real-time streams of data. The document then covers Twitter Storm, a platform for doing real-time computation on data streams. Key concepts of Storm like spouts, bolts, streams and topologies are explained. The document provides examples of using Kafka and Storm together to process tweets in real-time, including capturing tweets with keywords and counting hashtag occurrences. It concludes with a brief overview of Trident, a high-level API built on Storm.