What is the Parameter E in the G-code of Repsnapper?

Hi,
i am very new to this software Repsnapper.
After loading the stl file, and converting into the G-code i am able to get the G-code.
but in G-code What is the Parameter 'E' indicates.

can any one give clear defintion for the parameter E. and i need any help file regarding to the software where can i get it.

It's the mm of filament the extruder extrudes, either per command ("relative E-code") or cumulative

E codes are used during Printing progress

It denotes how much length of PLA or ABS to be extruded during Printing

Initially E codes are set to E0
E1.0000 denotes extrusion of 1mm PLA/ABS

if you need to extrude 1mm more then E code should be E2.0000

i.e., incrementing the values whenever you need the extrusion

if the next value is E1.5000 the extruder sucks back the PLA about 0.5mm

You can vary the Extrusion Multiplier in Printer settings and convert to Gcode to increment or decrement the Extrusion length in percentile during printing (It works during printing)