Traditional control systems are nowadays becoming in global data sharing solutions based on open platforms and free data repositories. In this context, Arduino is one of the most employed electronic devices in order to implement simple control solutions. This platform includes the most common communication ports (like UART or I2C) and supports the most popular communication protocols such as MQTT. This course describes all these details and shows how designing and implementing control system using Arduino devices. Moreover, the technique to connect to the global Internet the constructed control systems and allow a global data sharing is also described.