Page "Atanasoff–Berry Computer" Paragraph 15

Although the Atanasoff – Berry Computer was an important step up from earlier calculating machines, it was not able to run entirely automatically through an entire problem.

An operator was needed to operate the control switches to set up its functions, much like the electro-mechanical calculators and unit record equipment of the time.

Selection of the operation to be performed, reading, writing, converting to or from binary to decimal, or reducing a set of equations was made by front panel switches and in some cases jumpers.