KiCad generalities
Surface Mount Technolohy (SMT): There are no leads, with components soldered to one layer. Printed circuit board (PCB): conductive tracts or traces, generally copper that is laminated over generally fiberglass with fire resistant resin grade IV (FR4). Through electroplating is possible to make holes coated in copper, called plated-through hole (PTH). To avoid short-circuits solder mask is applied (lacquer-like polymer, generally green). Spared areas of polymers are meant to be soldered are called solder-mask keepout. To guide or for aesthetic reasons a silkscreen layer is added.
PCBs are created in a computer-aided (CAD) design software.
.sch: schematics
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