Noise Filtering in the Circuit - Capacitor or Inductor?

Both the Capacitors and Inductors can  be used to filter the noise. In this case, how would you decide whether to use inductor or capacitor for filtering the noise?

Using inductor or capacitor for filtering depends on the load for which the protection against noise is to be provided. The load impedance could vary based on the design specification. As inductor is connected in series, one has to remember that it has to provide maximum impedance to the noise frequency to be filtered and this inductor impedance must always be more than the load connected beyond it. So inductor is always preferred in cases where the load impedance is less. In the case of capacitor, to filter the noise, the impedance should be very less,so, the capacitor connected in parallel should always have lower impedance than the load connected beyond it. So, capacitor must be used when the load impedance is very high. Again, the typical scenario here is that the frequency of noise is very important. Whether it be inductor or capacitor, the component used must provide high impedance at that noise frequency. Now a question may come up from designers that we have used inductors in series without bothering about the load impedance. In this case, you must have used high value of inductor which suits the impedance requirements. This occupies space as well as adds cost to the circuit. 

One has to understand the electrical characteristics of the component to understand it's functionality before using in any application.