Proto-Arabic is the name given to the hypothetical reconstructed ancestor of all the varieties of Arabic attested since the 9th century BC. There are two lines of evidence to reconstruct Proto-Arabic: * Evidence of Arabic becomes more frequent in the 2nd century BC, with the documentation of Arabic names in the Nabataean script as well as evidence of an Arabic substratum in the Nabataean language. * The Safaitic and Hismaic inscriptions were composed between the 1st century BC and the 4th century AD, in the basalt desert of the northwest Arabian Peninsula and the Southern Levant. They are also crucial to the reconstruction of Proto-Arabic, since they show many features that are shared by epigraphic Old South Arabian and Classical Arabic. The common features set them apart from languages