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
Software calculator machines. The most recent hardware calculators are electronic hand-held devices with buttons for digits and operations, and a small window for inputs and results. The first software calculators imitated these hardware calculators by implementing the same functionality with mouse-operated, rather than finger-operated, buttons. Such software calculators first emerged in the 1980s as part of the original Macintosh operating system (System 1) and the Windows operating system (Windows 1.0). Some software calculators directly simulate one of the hardware calculators, by presenting an image that looks like the calculator, and by providing the same functionality. There is now a very wide range