Really the only thing preventing the construction of a <i>true</i> Turing machine is the inability to have an infinitely long tape. Fortunately, that limitation isn&#x27;t a problem in practice for most things you&#x27;d wish to compute.<p>At it&#x27;s simplest a Turing machine consists of an infinite tape of memory cells, a read&#x2F;write head, a state register, and a state transition table (functions). Read the current cell and look up the pair (current state, cell value) to get the effect (new cell value, direction to move head [left, right, stay], new state).<p><i>Nothing</i> in real computers can&#x27;t be translated to a Turing machine description. It just won&#x27;t be efficient :P. And anything written for a Turing machine will run on a real computer, modulo memory available.