The purpose of an OS is to provide an execution environment with a particular set of invariants / guarantees. This encompasses everything from "you can't read another process's memory" to "there is a consistent way to ask the user for money".
The purpose of an OS is to provide an execution environment with a particular set of invariants / guarantees. This encompasses everything from "you can't read another process's memory" to "there is a consistent way to ask the user for money".