Burroughs Class 7 Bookkeeping Machine, circa 1935

Bookkeeping machines were the precursors to the computer -- they processed and moved complex numeric and alphabetic data. Combining elements of typewriters, adding machines, and calculators, bookkeeping machines processed payroll, taxes, and recorded payments and billing. Efficient and reliable, these devices eased the workload of office workers. They were also used as vote tabulators and for complex calculation of scientific data.