Naked machine

A bare metal machine, in computer science, means when there is no core (S.O.) installed in the hardware. They are usually simple systems, that execute some task when an interruption occurs, and that the rest of the time they execute a very basic idle task, usually that does nothing. It is also used in cloud systems when starting a machine with no operating system in the cloud to include virtual machines.

In bare machines, state machines are often used. That is, it is assumed that the behavior of our machine can be modeled as a state machine. The interrupt routine would give us the status it needs to change. This was very popular, there are even tools that automatically generate the code of changes between states. But it's not a good idea for complex applications.

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