Input
Electronic calculators contain a keyboard with buttons for digits and arithmetical operations; some even contain "00" and "000" buttons to make larger or smaller numbers easier … See more

Precursors to the electronic calculator
The first known tools used to aid arithmetic calculations were: bones (used to tally items), pebbles, and counting boards, and the abacus, known to have been used by Sumerians and Egyptians before 2000 BC. Except for the See more

• Calculator spelling
• Comparison of HP graphing calculators
• Comparison of Texas Instruments graphing calculators See more

In general, a basic electronic calculator consists of the following components:
• Power source (mains electricity, battery and/or solar cell)
• Keypad (input device) – consists of keys used to input numbers and function commands (addition, multiplication See more

The fundamental difference between a calculator and computer is that a computer can be programmed in a way that allows the program to take different branches according to intermediate results, while calculators are pre-designed with specific functions (such as See more

In most countries, students use calculators for schoolwork. There was some initial resistance to the idea out of fear that basic or elementary arithmetic skills would suffer. There remains disagreement about the importance of the ability to perform calculations in the … See more

• U.S. Patent 2,668,661 – Complex computer – G. R. Stibitz, Bell Laboratories, 1954 (filed 1941, refiled 1944), electromechanical (relay) device that could calculate complex … See more