What does the letter C and E in the calculator represents?

Answer 1

C stands for Clear. A button labelled C is often used to erase the number you are entering, in case you make a mistake. Pressing it twice will erase the whole expression you are entering.

E usually stands for Error. The letter E is displayed on screen of most four-function and scientific calculators when there is a problem evaluating the expression, for example, if it exceeds the calculator's numeric range or you try to divide by zero.

A button labelled CE usually clears the number you are currently entering so you can start again, but on four-function calculators it can also release the E symbol from the screen so you can continue working.