A machine that provides arithmetic capabilities. The most basic calculators, which can cost pennies to purchase, add, subtract, multiply and divide. More advanced devices handle sines, cosines and other trigonometric functions. Whether mechanical or electronic, all calculators accept numeric input from dials, levers or a keypad. The results are displayed as mechanical digits, on punched paper tape or on a screen, such as an LCD. Unlike computers, calculators perform a finite set of functions, and they cannot handle text.
The First Handheld
In 1967, Texas Instruments introduced the first handheld calculator. The opened unit in the picture shows the paper tape used as output. (Image courtesy of Texas Instruments, Inc.)
The Curta Pepper Grinder
Completed in a World War II concentration camp in the 1940s, Curt Herzstark was given permission to perfect the calculator he patented earlier. These mechanical marvels were used up to the 1980s for their accuracy and ruggedness in hostile conditions such as car rallies. The sliders on the side hold the number multiplied by the number of times the "grinder" on top is turned. The mechanical results appear on top as well. (Image courtesy of Clive "Max" Maxfield, www.clivemaxfield.com)