Siri, the new Apple iPhone 4s voice assistant so much in the news, is a comforting female vocalist. So is the disembodied coo alerting you that your car door is ajar. As is nearly every other computer voice in just about every other modern device.

While there are several reasons for the feminine pitch, one of the most interesting is the influence of HAL, the vicious “male” computer in Stanley Kubrick’s famous movie 2001: A Space Odyssey.