"Purpura" refers to a polyetiological clinical picture characterized by haemorrhages of the skin.
The onset of purpura can be acute or chronic and insidious.
Purpura can be localized or disseminated, small spots or extensive.
A single purpura lesion can be flat (spot) or elevated (papule/plaque = palpable purpura), inflammatory (vasculitis) or non-inflammatory (e.g. due to a vasculopathy).
In a broader sense, independent diseases are also referred to as "purpura", which are associated with bleeding into the skin (e.g. purpura pigmentosa progressiva; purpura Schönlein-Henoch).