Amazon Kinesis is a cloud-based service that allows users to process and analyze real-time streaming data. It helps businesses collect, process, and analyze large streams of data quickly, enabling them to gain insights and make decisions in real time. The service supports various data sources, such as IoT devices, web applications, and logs, making it versatile for different use cases. With Amazon Kinesis, users can build applications that respond to data as it arrives, enhancing their ability to react to changing conditions and trends.