1e+ is the number of zeros for example 10 is 1e+1 it have only 1 zeros 1eX is the size of the 1e+ example is that 1e+1000 is 1eX3 the number of zeros in 1e+ 1e^ is a large like 1e+10(1e+100000000000) same as the 1eX for the + 1e^1 is 1eX10 or 1e+100billion 1e- 1e/