Defining when the first computer was invented depends on how you define “computer.”
Some would say that there was evidence of the first computer in the mid 1800s. But most of us would probably argue that the definition of the computer then is pretty far off from what we would call a computer today.
Possibly the most commonly agreed upon beginning of the modern computer is the story of J. Presper Eckert and John Mauchly inventing the first digital computer, called ENIAC, in 1943. It occupied 18,000 square feed and weighed almost 50 tons.
A lesser-known fact is that in 1936, Vladimir Lukyanov built an analog computer powered by water.
Back then, before the miniaturization of transistors, computers had a more visible system of counting. Things like gears, pivots, beads and levers were often used, but they needed some sort of power to function.
The Water Integrator functioned by careful manipulation of water through a room full of interconnected pipes and pumps. The water level in various chambers, with precision to fractions of a millimeter, represented stored numbers, and the rate of flow between them represented mathematical operations.
Adjusting taps and plugs altered the flow of water while the end result was seen by measuring the level of water in certain tubes.
The Water Integrator was originally designed to solve the problem of cracking in concrete and can now be found in Moscow’s Polytechnic Museum.