Foregrounding is a concept in literary studies concerning making a linguistic utterance stand out from the surrounding linguistic context, from given literary traditions or from more general world knowledge. It is "the 'throwing into relief' of the linguistic sign against the background of the norms of ordinary language." There are two main types of foregrounding: parallelism and deviation. Parallelism can be described as unexpected regularity, while deviation can be seen as unexpected irregularity. As the definition of foregrounding indicates, these are relative concepts. Something can only be unexpectedly regular or irregular within a particular context. This context can be relatively narrow, such as the immediate textual surroundings or wider such as an entire genre. Foregrounding can occur on all levels of language. It is generally used to highlight important parts of a text, to aid memorability and/or to invite interpretation.