Double panel is thin circuit board, the two sides of the double-sided PCB (Double-Sided boards are a wiring. But to use wires on both sides, between the two sides must be in the appropriate circuit is connected to. This circuit between the "bridge" is called the guide hole (via). The guide hole is on the PCB, full of small holes or coated with metal, it can lead and both sides of the connection. Because the double sided area than a single panel a times, but because the wiring can be mutually staggered (around to the other side), it is more suitable for use in circuit is more complex than a single panel.
Strict sense double-sided board is a circuit board is very important in a PCB board. His purpose is big, see a PCB board is double sided board is also very simple, I believe that friends of the single panel understanding can fully grasp and double panel is an extension of single panel, meaning single panel lines is not enough to go negative, double-sided board, there are important characteristics is a via hole. The simple point that is double line both sides of the line! A sentence is generous including: double line board is double sided board! Some friends will ask such a board double line, but there is only one electronic parts, this board is double sided board or single panel? The answer is obvious, so the board is just in the plate with double-sided plate, double-sided board on the parts.