In French, a bureau is a desk, so bureaucracy means basically "government by people at desks". Despite the bad-mouthing they often get, partly because they usually have to stick so close to the rules, bureaucrats do almost all the day-to-day work that keeps a government running.
The idea of a bureaucracy is to split up the complicated task of governing a large country into smaller jobs that can be handled by specialists.
Bureaucratic government is nothing new; the Roman empire had an enormous and complex bureaucracy, with the bureaucrats at lower levels reporting to bureaucrats above them, and so on up to the emperor himself.
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