Euler was Swiss and spoke French, so he might have called the function "le

**Logarithme Naturel**", rather than "the natural log", in which case, "ln" makes sense. However, history shows that Euler actually used just "l(x)" for the logarithm using "his" number e as its base.So, what is M and M+ on a calculator?

Old or simple

**calculators**have a memory register - essentially a second**calculator**that can handle addition/subtraction only.**M+**, M-: Add (or subtract) the current value to (or from) the stored value in the memory register. MR : Recall the current memory register value. MC : Clear the memory register (set to zero).What is the meaning of AC in calculator?

- All Clear. Clears the

**calculator**, and resets any functions. The contents of the memory are not affected by**AC**. The memory can be cleared after pressing**AC**by pressing Min.What do the MS mean on a calculator?

The ms (

**memory store**) button copies the number from the screen to the memory. The mr (memory recall) button brings the memory value back to the screen. M+ and m- add or subtract the screen value from the memory value (hiding the result in the memory, so you need to be careful not to double-press the button).