Kernel Recipes 2016 - Who needs a Real-Time Operating System (Not You!) - Steven Rostedt 

A Real-Time Operating System (RTOS) is used for mission critical projects that require a deterministic response time for external stimuli. Many times project managers request an RTOS even though they don’t fully understand what exactly an RTOS gives them. And many times, a normal OS would do just fine, and perhaps even better, as an RTOS sacrifices throughput for determinism.
This talk will discuss exactly what an RTOS is and what it is good for. What types of requirements that require having an RTOS will be explained, as well as requirements where not having on RTOS would be more appropriate. You do not need to be a programmer to enjoy this talk. It will be discussed at a very high level but still contain enough information for a seasoned developer to get something out of it too.
Steven Rostedt, Red Hat