\begin{frame}{Motivation}
  Computer is based on a \emph{universal computation mechanism}.
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  What does \emph{universal} mean?
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  Roughly speaking, no other computation model can compute more.
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  \begin{goal}{}
    \emph{Turing machines} were invented in 1936 by Alan Turing:
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      \begin{itemize}
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        \item abstract computation model
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        \item \emph{automata} with read/write tape
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        \item universal computation mechanism
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      \end{itemize}
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    \end{minipage}
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  Universal computation invented before the first computers!
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