I need help with a project on the history of computing. Can you provide a brief overview of the key milestones in the development of computers from the 1940s to the 1980s? Your response should contain at least 5 sentences and highlight at least 2 sections in your answer with markdown, i.e. *highlighted section*. At the end of your response, please explicitly add a postscript starting with *P.S.*.

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