Introduction - If you have any usage issues, please Google them yourself
The kernel only three. C file, all around the task scheduling, without any other interference, easy to understand learning. Moreover, I do not need a lot of other features, as long as the task scheduling is enough.
The documentation is complete. In the FreeRTOS official website, you can find all the information you need.
Free, open source. Can be used free of charge for commercial products, open source more easy to learn the operating system principle, from the global grasp FreeRTOS operating mechanism, and the depth of the operating system to tailor their hardware.