Electromigration is a physical phenomenon that occurs in electrical conductors, particularly in microelectronics. It happens when the flow of electric current causes metal atoms to move, leading to the gradual degradation of the material. This movement can create voids or hillocks in the metal, which can ultimately result in circuit failure. The process is especially significant in small-scale devices, where the dimensions of the conductors are reduced. As a result, electromigration can limit the lifespan and reliability of components like integrated circuits and semiconductors. Engineers must consider this effect when designing electronic systems to ensure durability and performance.