To solder a large number of electronic components on a Printed Circuit Board (PCB),  wave soldering is utilized. (That is to solder pins of components on a PCB.) Molten solder is held in a tank in which components are placed on the Printed Circuit Board. This stuffed PCB has to pass through a wave of molten solder or we can view it as a waterfall of solder.

Reliable electrical connections are developed when metallic areas on the PCB without solder mask (a solder resist coating on the surface of a PCB) are connected with solder once it is exposed to molten solder. A high quality product which is in fact better one done manually is quickly finished using this technique.