<human>:  I have a question about the history of computational thinking. Why did Alan Turing invent the Turing machine?
<bot>: The Turing machine was invented to prove that the Church-Turing thesis was true. The Church-Turing thesis is that any algorithm can be expressed as a machine that can be built. The Turing machine was designed to be a universal machine, meaning that it could simulate any other machine.