What are the different types of operating systems?

Answer:

There can be an infinite number of "types", depending on how you want to classify them. Free or proprietary? Realtime? Unix-like? 16, 32, or 64-bit? Server, desktop, or embedded? By kernel type? This question can't really be answered without better context.
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First answer by ID2057490712. Last edit by SudoKing. Contributor trust: 173 [recommend contributor recommended]. Question popularity: 73 [recommend question].
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