title: What is the difference between an embedded program with RTOS and without RTOS
body: <p>Can anyone explain to me what is the difference between an embedded program with and without RTOS. As when i start learning embedded, I always write code without any OS, all code is separated in to sub function and main function, sub function is called inside main function and it still run correctly, why does it still run without OS? And if I add RTOS to my code, what would happen? All answers are appreciated, thank you so much</p>