Calculator calculator marketed to the Real Estate industry with preprogrammed functions to simplify the process of calculating payments and future values. In 1985, CI launched a calculator for the construction industry called the Construction Master which came preprogrammed with common construction calculations (such as angles, stairs, roofing math, pitch, rise, run, and feet-inch fraction conversions). This would be the first in a line of construction related calculators. The first desktop "programmable calculators" were produced in the mid-1960s by Mathatronics and Casio (AL-1000). These machines were very heavy and costly. The first programmable pocket calculator was the HP-65, in 1974; it had
The Millionaire Calculator The Millionaire Calculator The Millionaire calculator was the first commercially successful mechanical calculator that could perform a direct multiplication. It was in production from 1893 to 1935 with a total of about five thousand machines manufactured. The principle of a calculation machine with progressive transmission of tens was invented by Chebyshev and demonstrated at the 1878 World's fair in Paris. In 1881 Chebyshev demonstrated a model of the calculation machine with automatic multiplication but did not take out a patent for it. In 1834 Luigi Torchi of Milan invented a direct multiplication machine. The first patented multiplying machines was due