Question: How do calculators work?

Ian van der Linde answered on 24 Jun 2011:

Calculators are basically little computers. They contain a microprocessor that runs a program. In the microprocessor, numbers your type in and the answers you have calculated are held in a small memory. In that memory, numbers are represented in binary (a series of 0s and 1s). When you press the keys on the calculator, you change the routine that the microprocessor runs – the binary number in memory is taken and passed through a component called the ALU (arithmetic and logic unit), which is able to perform maths operations by shifting the binary number left and right and masking it with other binary numbers. It can accomplish all manner of sophisticated maths tasks by repeatedly doing these simple operations in a specific order. Quite amazing really!