Gcode assistance need : r/3Dprinting

Was watching Futurama when I noticed this! That's G-Code! : r/3Dprinting

r Develops Open Source Custom G Code Generator For 3D Printing

Guide: Poor mans multi material (What to edit in the gcode) : r/3Dprinting

Most used 3D Printer G-Codes - Commands detailed

does my gcode need to include something about taking in the bed leveling into account or does the printer just know already. someone told me that I need to include a line

How to 3D Print Highly Complex Parts using G-Code Injection — The Mantis 3D Printer

G-Code for retract filament : r/3Dprinting

I've Made a Free and Open-Source GCode Importing Tool for Blender : r/ 3Dprinting

G-code Basics for 3D Printing — CNC Kitchen

Guide: Poor mans multi material (What to edit in the gcode) : r/3Dprinting