The only working reproduction of the world’s first electronic digital computer goes on display in Iowa City today. The Atanasoff Berry Computer or A-B-C is a one-of-a-kind device, built at Iowa State University between 1939 and ’42. This replica took about as long to build.I-S-U professor John Gustafson was on the team that rebuilt the A-B-C. He says it’s a must-see item for anyone who can appreciate history and how far we’ve come in the electronic age.The computer was built long before there was a ‘net to surf, though Gustafsonjokes it runs on Windows ’39. The original A-B-C was designed to solvescientific equations. The A-B-C will be shown and run at Iowa City’sdowntown Holiday Inn between 5 and 7 p-m at an I-S-U Alumni Association reception.