Cameron has written about some of the problems with defining a computer today, but as some people remember computers used to be people. In fact, that is is the earliest definition: "A person who makes calculations or computations", from the earliest 17th century (thank you OED). It was only in the mid 20th century that the word included electronic devices.
If we pick up the story in the late 19th century, computing had become a highly gendered occupation for women. Many were highly-educated mathematically-inclined but unable to work elsewhere in academia. A typical position for computers was to carry out astronomical calculations on behalf of male astronomers.
Computing was considered an anonymous clerical position for the most part, and since history is typically written by "the winners", we don't really know much about these women. Fortunately, in the last few decades, historians have been working hard to find their stories and rightfully add women back to the history of science and technology.
Hidden Figures is a new movie coming out early next year that features the story of human computers who worked at NASA early in the 20th century space race. Check it out (pay attention at 1:28 or so when the main character is described as a computer):
Of course, as you can see, aside from sexism this movie is also going to do is take up the challenge of racism: many of the female computers at NASA were Black. It looks like a bit of a feel-good movie with a message, but I'm looking forward to it. If you'd like know more, you might try http://nobrocomputing.tumblr.com/ a blog dedicated to this very topic. It will lead you to all sorts of interesting stories of underappreciate women in the history of computing. You might also try watching the Bletchley Circle, a fictional mini-series about underappreciated women who helped decode messages during WWII.