The ENIAC The ENIAC is the first modern computer. It was built in 1946 at the University of Pennsylvania. The machine was very big. It was the size of a large room and very heavy The ENIAC weighed more than 27, 000 kilograms. It was very expensive. Plus, it was not easy to use. But it is important in the history of computers. Over the years, computers got smaller and smaller. They also got cheaper and cheaper.First, big businesses got computers. Then, small businesses bought them. Now, people have computers at school, office, and home. Our small computers are much faster than the ENIAC now. But we still remember it.