Thinking Space

Early electric computers used the vacuum tube, a lightbulb-like metal filament enclosed in glass. The electric current running through the tube could be switched on and off. A tube turned on was coded as a 1 while a vacuum tube turned off was a 0. These two digits could produce any number using a system of binary counting.

Because vacuum tubes glowed like lightbulbs, they attracted insects requiring regular ‘debugging’ by their engineers. Since then the term has been adopted to refer to the process of identifying and fixing errors in computer programs and systems.