Hayyuwj is a 10th century Hebrew scholar and linguist who was born in Fez, North Africa c945. He migrated to Cordova, Spain c960, where he studied, taught and wrote on Hebrew linguistics and biblical matters. He died in around the year 1000. He is a pivotal figure in the history of Hebrew linguistics, in that he abandoned the traditional linguistics methods and adopted and adapted the more sophisticated linguistic paradigm developed by the 8th century Arab grammarians of the School of Basrah. He was the first Hebrew linguist to apply the newly realized formal linguistic methods to the analysis of Biblical Hebrew text. He wrote two detailed treatises on the weak and doubled verbs of Biblical Hebrew: kita:b 'al-'af`a:l dhawa:t Huru:f 'al-liyn, and kita:b 'al-'af`a:l dhawa:t 'al-mithlayn, and a treatise on selected biblical topics: kita:b 'al-nutaf. He also wrote this gem of a treatise on tanqiyt, the textual pointing system of the biblical text that was developed by the Masoretes to indicate vowels, accents, and prosodic features in the otherwise purely consonantal system biblical text and gave it a clear statement and a coherent basis. This is a singular treatise and one of a kind, written in Arabic about Hebrew vowels, called Haraka:t 'motions', using the Semitic paradigm of analysis. He wrote clearly and elegantly on an obscure, intractable and neglected topic that has engaged the Biblical scholars ever since.