Slicing

3D printers take .gcode files as input. The purpose of the slicing is to convert your 3d model (commonly in .stl format) into .gcode that the 3D printer can understand. 

There are many different kinds of slicers. If you're using a Creality brand printer you will need to use Creality Print, however for all other machines the most common slicer at MCI is Prusa Slicer. Click on the links for the slicer you're using to access the MCI guide for it.