Isn’t it funny that a computer was like your office accountant before it became a device? 

The first time the word ‘computer’ was ever used according to the Oxford English Dictionary was in 1613 in a book titled; ‘ The Yong Mans Gleanings’ by Richard Braithwait. 

Braithwait, who was an English writer wrote in his book: “I have read the truest computer of times, and the best Arithmetician that ever breathed.’’

Computer is no longer a human but an electronic device. (madamenoire)

It’s like Braithwait knew someone, may be a friend, who was very good at calculations and computations and earned a living from his/her understanding of numbers. Basically, computer was a human and its usage back then was more like a job title. 

According to Wikipedia, the word continued to be used as a job title until the middle of the 20th century. At that time, many women were hired to work as computers and by 1943, most human computers were young women.

A woman using computer for her task. (fabwoman)

From the end of the 19th century the word slowly began to assume a different identity and a new meaning. Young women who worked as computers were no longer referred to as computers. A machine, an electronic device for storing and processing data took their job role and assumed their job identity.

This led to the modern day use of the device to mean “programmable digital electronic computer” and this usage according to The Online Etymology Dictionary dates back to 1945.