On December 4, 1974, a hapless pizza restaurant worker answered the phone and heard a strange, robotic voice. "I'd like to order a pizza," the voice said. "A large pizza, please. Pepperoni and mushrooms." The worker asked for the address, but then hung-up when the voice took too long to respond.

The caller on the other end was Donald Sherman. But it wasn't his voice. He had a rare disorder called Möbius syndrome, which results in facial paralysis and makes speech difficult. Sherman was calling from the Michigan State University's Artificial Intelligence Laboratory, where he was using one of the very first text-to-speech systems to try to order a pizza.

Sherman was using a system designed by John Eulenberg and J. J. Jackson and consisting of a CDC 6500 mainframe computer nicknamed "Alexander" and a device called the Votrax voice synthesizer.

The first few places Sherman called thought it was a prank, but at last someone took the call seriously. Alexander could speak clearly enough to place the order, and the pizza was delivered.

It was the first time anyone used a computer to order a pizza, and more importantly, it proved that text-to-speech systems could be used to effectively communicate in the real-world. Forty years before Siri.