How do I view layers in ExpressPCB?

On a double sided board, the pads of a through-hole component are on both the top and bottom layers.  That way you can connect a trace to a pin when the trace is on either layer.  The view you see is of the top side of the board.  The top layer is shown in red and the bottom in green.  You will notice that if you turn off the top layer display in the “Options” dialog box the pads will turn green. The top layer is the component layer.  The bottom layer is shown in x-ray view.

We also recommend that you read the online help within the ExpressPCB program.  Look for the topic, “Understanding the Layers of the PCB.”