A PCB circuit board is the backbone of electronics. The same term is now used for printed wiring cards and printed wire boards as well. The PCBs play an important role in all types of devices that use some kind of electronics to function. Developers of such products have to know the types of materials available for making these boards. They have to take great care in selecting the right material or it can result in failure of the end product. Any such failure can result in heavy losses to the manufacturer if it necessitates product recalls.
There are four layers in most PCBs. The first is the substrate on which this board is built. A thin copper layer as per the PCB design is laminated and etched on it to pass the current and signal. A layer of soldermask polymer is applied on the copper traces to prevent oxidation and solder bridge formations between closely placed solder pads. Silkscreen on top is used to print the letters, numerals and graphics to indicate how and where to place the components.