ENIAC

It was invented in 1945 by Eckert/Mauchly

It helped the US Army by calculating artillery firing tables.ENIAC was first to be used for mililtary. Also, it could solve a lot of different numerical problems. It stands for Electro-Numerical Integrator And Computer

It was a predecessor for many computers to come.

References

https://en.wikipedia.org/wiki/ENIAC