Once all the traces are placed, it is time to check the routing of every signal to verify that nothing is missing or incorrectly wired (missing vias, unconnected pads, short circuits, etc.). Generally, all CAD software packages usually incorporate layout design tools such as the Design Rule Check (DRC).
The Design Rule Check (DRC) is a powerful automated feature that checks both the logical and physical integrity of a design.
The Design Rule Check (DRC) should be used on every routed board to confirm that it satisfies a series of recommended parameters called design rules.
The design rules are a series of parameters (limitations) provided by the PCB manufacturer. A Design Rule Check allows you to establish a set of boundaries for trace widths, component spacing, via diameters, etc.