From Turing’s Proposal for Development in the Mathematics Division of an Automatic Computing Engine (ACE):
“Calculating machinery in the past has been designed to carry out accurately and moderately quickly small parts of calculations which frequently recur. The four processes addition, subtraction, multiplication and division, together perhaps with sorting and interpolation, cover all that could be done until quite recently, if we except machines of the nature of the differential analyser and wind tunnels, etc. which operate by measurement rather than by calculation.
It is intended that the electronic calculator now proposed should be different in that it will tackle whole problems. Instead of repeatedly using human labour for taking material out of the machine and putting it back at the a ppropriate moment all this will be looked after by the machine itself. This arrangement has very many advantages.
(1) The speed of the machine is no longer limited by the speed of the human operator.
(2) The human element of fallibility is eliminated, although it may to an extent be replaced by mechanical fallibility.
(3) Very much more complicated processes can be carried out than could easily be dealt with by human labour.
Once the human brake is removed the increase in speed is enormous. For example, it is intended that multiplication of two ten figure numbers shall be carried out in 500 μs. This is probably about 20,000 times faster than the normal speed with calculating machines.”