Four ways an Arabic surname forms
Arabic family names typically arise in a few ways: a patronymic using bin/ibn (“son of”) or bint (“daughter of”); a nisba — an origin name ending in -i that points to a place or tribe (Baghdadi, “from Baghdad”; Halabi, “from Aleppo”); an occupation, often with al- (“the”) — Haddad, “the blacksmith”; Najjar, “the carpenter”; and a descriptive name of a virtue or quality (Karim, “generous”; Amin, “trustworthy”).
Transliteration and the names of God
Because Arabic uses its own script, spellings vary widely in the Latin alphabet (Mohammed, Muhammad, Mohamad are the same). Several surnames echo the beautiful names of God, often as Abd al- (“servant of the”) — as in Abd al-Rahman, “servant of the Most Merciful.”