This document discusses stream processing using Hazelcast Jet. It begins with an introduction to stream processing and Hazelcast Jet. It then provides examples of word count and Twitter sentiment analysis to demonstrate Jet's capabilities. It discusses how Jet works under the hood and handles infinite streams and windowing. It also covers deploying Jet on Kubernetes and provides use cases like a stock trade aggregator and web crawler. Overall, the document provides an overview of Hazelcast Jet for stream processing and examples of how to use it for various tasks.