An adding machine is a machine designed to perform simple mathematical operations such as adding, subtracting, multiplying, and dividing numbers, particularly numbers representing monetary units, in large or small groups. They are usually configured for use in office or business settings with a simple keypad of digits from 0 to 9 and keys for the basic mathematical functions. An adding machine will often have an integral mechanism for printing all calculations on a small roll of paper. Older adding machines worked purely by mechanical means, but newer machines of this type are generally electronic digital devices.
The first mechanical calculator, the precursor to adding machines, was invented by Blaise Pascal in the 17th century. Further improvements were implemented by other inventors over the next two centuries until the first widely available commercial adding machine was introduced at the end of the 19th century. Early adding machines were very complex and required a crank or lever to be pulled after each operation, which would result in the total being displayed. The next operation was then keyed in and the crank or lever pulled again. The first adding machine with an integral device for printing the operations and their results as they were performed was introduced in 1872.
Accountants and bookkeepers use adding machines to make their jobs easier. Adding machines reduce the possibility of error as long as the numbers are keyed in properly, allowing the operator to manipulate a large series of numbers quickly. These devices were common in almost every business for many decades and, in one respect are still, as the common cash register is one type of adding machine.
This mechanical type of adding machine was common until electronic and digital devices allowed electronic adding machines to be more cheaply manufactured than their older mechanical counterparts. This transition began in the 1960s and 1970s. Bookkeepers and accountants still use adding machines in 2011, although their use is becoming less common as more and more of their functions are taken over by accounting software and other computer programs. Today, software adding machines that mimic the functions of older, traditional adding machines are available on the internet and even allow users to download and print a record of all operations.