It covers approximately 2,000,000 km2 (770,000 sq mi) and is inhabited by roughly 115 million people (Ethiopia: 96.6 million, Somalia: 10.4 million, Eritrea: 6.4 million, and Djibouti: 0.81 million). Regional studies on the Horn of Africa are carried out, among others, in the fields of Ethiopian Studies as well as Somali Studies.
This peninsula is known by various names. In ancient and medieval times, the Horn of Africa was referred to as the Bilad al Barbar ("Land of the Berbers"). It is also known as the Somali peninsula, or in the Somali language, Geeska Afrika, Jasiiradda Soomaali or Gacandhulka Soomaali. In other languages that are local or adjacent to the Horn of Africa, it is known as የአፍሪካ ቀንድ yäafrika qänd in Amharic, القرن الأفريقي al-qarn al-'afrīqī in Arabic, Gaaffaa Afriikaa in Oromo and ቀርኒ ኣፍሪቃ in Tigrinya. The Horn of Africa is sometimes shortened to HOA. The Horn of Africa is quite commonly designated simply the "Horn", while inhabitants are sometimes colloquially referred to as Horn Africans. Sometimes the term Greater Horn of Africa is used, either to be inclusive of neighbouring northeast African countries, or to distinguish the broader geopolitical definition of the Horn of Africa from narrower peninsular definitions. Ancient Greeks and Romans referred to the Somali peninsula as Regio Aromatica or Regio Cinnamonifora due to the aromatic plants, or Regio Incognita owing to its unchartered territory.