📄️ Annular ring📄️ Drill bit and drill hit📄️ Gold Fingers📄️ Design principles introduction📄️ Keep-out areas📄️ Pads and holes📄️ Panel📄️ PCB materials and FR4📄️ Pick-and-place📄️ Schematic symbols📄️ Silkscreen📄️ Surface mounted devices📄️ Solder mask📄️ Solder paste and stencil📄️ Traces📄️ Via