Market leading RTOS (Real Time Operating System) for embedded systems with Internet of Things extensions. Real-time operating system for microcontrollers?

Developed in partnership with the world’s leading chip companies over an 18-year period, and now downloaded every 170 seconds, FreeRTOS is a market-leading real-time operating system (RTOS) for microcontrollers and small microprocessors. Distributed freely under the MIT open source license, FreeRTOS includes a kernel and a growing set of IoT libraries suitable for use across all industry sectors. FreeRTOS is built with an emphasis on reliability and ease of use.