In addition to that you will also find other markings on the pcb. In electronic circuits there are many electronic symbols that are used to represent or identify a basic electronic or electrical device. Because the electronics industry has not adopted a single symbology standard cie has included the most frequently used symbols that represent each component.
The abbreviation for a resistor r followed by a number to identify it on a pcb r102.
The symbol as initially created will represent the generic graphical features of a resistor but not the detailed functions of a specific resistor. They are mostly used to draw a circuit diagram and are standardized internationally by the ieee standard ieee std 315 and the british standard bs 3939. You will see the symbol for a resistor. When the pcb designer places that symbol onto a schematic the symbol is associated with the specific functional information such as resistance values and tolerances of the desired part.
