The Difference Machine

The difference engine

About the Difference Machine

The difference machine is considered by most to be the first computer in the world, and was the first complete design for an automatic calculator. The difference machine was a large, mechanical machine that was developed by Charles Babbage. It was used mainly to calculate and tabulate polynomial functions automatically, and was designed to make no errors in the process. It could not perform multiplication or division, but used repeated addition or subtraction in order to make up for this. The difference machine was designed to be powered by steam and as large as a train. While Babbage had finished his designs in 1830, he never managed to finish building his machine due to the limited funds. The machine was eventually finished in 1991.

How to use them

In order to use the difference machine, the user first had to program initial values to each of the columns in the difference machine. Then, the columns in the machine would rotate. The number of times they rotated depended on the operation and the operands. Once the machine had completed this process, it would automatically print out the results in the form of a table.

Photo Credits

http://www.computerhistory.org/babbage/engines/