Printed circuit board (PCB) mechanically supports and electrically connects electronic components or electrical components using conductive tracks, pads and other features etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate. Components are generally soldered onto the PCB to both electrically connect and mechanically fasten them to it.Printed circuit boards are used in all but the simplest electronic products. They are also used in some electrical products, such as passive switch boxes.Silkscreen is a layer of ink traces used to identify components, test points, parts of the PCB, warning symbols, logos and marks etc. This silkscreen is usually applied on the component side; however using silkscreen on the solder side is also not uncommon. But this may increase the cost. Essentially a detailed PCB silkscreen can help both the manufacturer and the engineer to locate and identify all the components.