Shunt resistors is applied  with the primary purpose to measure current.  However, the meaning of the term shunt in electronics is broader than that. A shunt is an element that is used in a circuit to redirect current around another part. The areas of application vary widely. For some applications, electrical devices other than resistors can be used. A few examples are given to illustrate the diversity of shunts.
 
  
Protecting a circuit against overvoltage
A method to protect a circuit from a too high voltage is using a crowbar circuit. When the voltage gets too high, a device will short circuit. This results in the current flowing parallel to the circuit. This causes immediately a voltage drop in the circuit. The high current through the shunt should
trigger a circuit breaker or a fuse.
 
Bypass electrical noise
Shunts with a capacitor are sometimes applied in circuits where high-frequency noise is a problem. Before the undesired signal reaches the circuit elements, the capacitor redirect the noise to the ground.
 
Bypassing a defective device
When one element in a series circuit fails, it will break the complete circuit. A shunt can be used to overcome this problem. The higher voltage that exists due to the failure will cause the shunt to short out. The electricity will pass around the defective element. A good example of this is Christmas lighting.