what does the E mean?
On a calculator? Depends. It could mean error or that the number is so big/small that you need scientific notation
In Maths, (I assume you mean 'e')
\(e=\displaystyle\sum^{\infty}_{0}\dfrac{1}{n!}\)
In Physics, E usually means energy like in the famous formula E = mc2
Btw the c in E = mc2 means the speed of light using the unit ms-1.
:)
