This in-depth workshop is an introduction into MQTT and shows you in a very practical manner how you can take advantage of the light weight IoT protocol. The workshop starts off with a theoretical part, introducing the basics of MQTT and its ecosystem (MQTT Broker, MQTT Clients, Tools). Afterwards we directly jump into action and everybody can experience first hand how it feels to build a MQTT client that sends and receives messages from a broker. During the practical coding examples we will build our own MQTT simulator with a common Java library. A second MQTT client which is using MQTT over websockets will display all simulator information in a real-time web dashboard. Ambitious participants can also use a MQTT library in their preferred programming language for implementing the MQTT simulator in the workshop because the basic principles are identical. Even if you have little programming knowledge you will learn how to leverage MQTT for your product or project.