If you want two interconnected PCB, PCB that is physically connected on the two circuits are generally required to known as "Goldfinger" edge connector (edge connector).
Goldfinger contains many exposed copper pad, the copper pads in fact is a part of the PCB wiring. The PCB on which a finger is inserted into the appropriate slot on another piece of PCB (commonly called slot Slot).
In the computer, such as graphics card, sound card or other similar interface cards are connected to the motherboard through the finger.
