This document discusses using Docker on Raspberry Pi for IoT applications. It begins by explaining why Raspberry Pi paired with Docker is useful for rapidly developing IoT apps in a portable way. It then demonstrates controlling an LED with Docker and GPIO pins on Raspberry Pi. Several Docker concepts and commands are explained like layers, images, containers. Various use cases for Docker on IoT devices are outlined like running services, development environments, computing tasks. It also touches on integrating Docker with MQTT and demonstrates continuous integration/delivery using Docker and CircleCI. It concludes by answering common Docker questions.