Question/answer found on Quora:
Question:
"If I wanted to develop an operating system, where can I start?"
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Reply:
Young Composer: "Herr Mozart, I am thinking of writing a symphony. How should I get started?"
Mozart: "A symphony is a very complex musical form and you are still young. Perhaps you should start with something simpler, like a concerto."
Young Composer: "But Herr Mozart, you were writing symphonies when you were 8 years old."
Mozart: "Yes, but I never asked anyone how."