The Best Resources About Through Hole PCBs
The through hole is a hole in an electrically conductive material through which leads are soldered, that is plated with a metal. The metal is occasionally chosen to be more corrosion-resistant than the solder. The other side of the board often has copper pads so that components can easily be soldered to the back side. Instead of making a surface mount version of a PCB, manufacturers can use through-hole components for certain applications, where it makes sense to have holes instead of pads.