what does e =

[potterfan3]

E=what

[Gef]

e = m c(squared)

e is energy; m is mass and c is the speed of light.

[PFD]

In the wonderful world of science, the symbol E or e has several meanings; it can be, amongst other things, almost any type of energy, elasticity, Young's Modulus, the symbol for an electron, the atomic potential, or simply a fundamental constant of mathematics, approximately equal to 2.7182818285...

[Dagman]

Or just a shorter version if "eee by gum!' a Yorkshiremans term of surprise ;-)