When you find that capacitors with the same value of capacitance come in packages ranging from the tiny SMT 0402 to those large radial packages, is there a difference? The reason I'm asking is that I'm trying to design my first standalone PCB project... and would like to use the smallest components possible, including things like capacitors. But when I look at commercial products, such as evaluation boards I have worked with in the past, some have very large capacitors in places (such as next to the voltage regulator) even though there are much smaller capacitors in other places. So it's made me wonder if there's some advantage or disadvantage associated with the physical size of a capacitor? What would you recommend for decoupling at the input/output of a voltage regulator? And what's a good value to use at the AREF pin? or AVCC pin? My datasheet speaks many times of placing one there for better noise suppression but does not mention a recommended value? Or package size, etc...?