Nanoscale technology nodes bring reliability concerns back to the center stage of digital system design. A systematic classification of approaches that increase system resilience in the presence of functional hardware (HW)-induced errors is presented, dealing with higher system abstractions, such as the (micro) architecture, the mapping, and platform software (SW). The field is surveyed in a systematic way based on nonoverlapping categories, which add insight into the ongoing work by exposing similarities and differences. HW and SW solutions are discussed in a similar fashion so that interrelationships become apparent. The presented categories are illustrated by representative literature examples to illustrate their properties. Moreover, it is demonstrated how hybrid schemes can be decomposed into their primitive components.