Cura engine contains the algorithm to convert the 3D models loaded on the build plate into printable gcode lines. Cura engine uses all inputs available in the user interface to create what you desire. Rotate, scale, and multiply objects, set the material profile and adjust the print settings to create a unique recipe for the 3D printer’s output.
Note: Cura 5 has a brand new slice engine with variable line widths. Please read this article on what changed within this version.