What's the difference between a riad, a dar, a kasbah, and a fondouk?

A riad (riyad, plural riyadat) is a traditional Moroccan house built around a central courtyard with a garden — riyad means garden in Arabic, and the structure takes its name from what's at the centre. Two storeys around an open square, fountain in the middle, citrus trees on the floor. What's marketed today as a riad-hotel is usually a converted family riad. A dar ("house") is the more general term for any traditional courtyard house, with or without a garden. Many "riad hotels" are technically dars — central courtyard, but tiled rather than planted. The distinction is taken loosely in tourism listings.

A kasbah is a fortress or fortified compound, originally a defensive structure with thick rammed-earth walls and corner towers. The Kasbah of Marrakech is a walled royal district built by the Almohads in the 12th century; the kasbahs of the Drâa and Dadès valleys (Aït Benhaddou, Telouet, Skoura) are family fortifications, ksar in the plural Berber form. The word also means "citadel" — Tangier's kasbah is the old hilltop quarter inside its own walls.

A fondouk (funduq) is a caravanserai: a courtyard inn for traders, with stables on the ground floor and sleeping rooms above. Fes still has dozens of working fondouks in the medina, now repurposed as artisan workshops, and Marrakech's Fondouk el-Nejjarine (Fes) and Fondouk Sla (Marrakech) have been restored as museums. They're the missing word when someone says, "This used to be where the camel trains slept."