This document provides an overview of common birthmarks and naevi (moles). It discusses the main types including melanocytic naevi (moles), vascular birthmarks like infantile haemangiomas and vascular malformations, Mongolian spots, and sebaceous naevi. While most birthmarks are harmless and need no treatment, some like large congenital melanocytic naevi, ulcerating haemangiomas, or vascular malformations associated with other conditions may require management with treatments like laser therapy or medications.