The introduction gives an account of Imam Al-Salmi, his contribution to hadith terminology. Then, broader terms are highlighted like Sunnah, hadith, tradition, vestige, reports, witnesses and follow-ups. The first chapter explores six types of hadiths according to authority like sacred, traceable anddiscontinued hadiths as wellintersected, musnad andconnected hadiths The second chapter reviews two types of hadithes based on the number and the characteristics of the narrators: mutawatir and ahad hadiths. The latter type includes three subcategories: gharīb, azizand mash-hur hadiths. Chapter three reviews accepted hadiths and their qualifications highlighting four types: authentic hadith, good hadith, extrinsically soundauthentic hadiths and good hadith. It also gives an account ofother types of accepted hadiths like perfect hadith, mukhtalif hadiths as abrogating and abrogatedHadiths Chapter four underpins types of rejected hadiths due to defects in the chain of narration or the integrity and the accuracy of the narrators. The first section of the chapter explores weak hadiths due to obvious defects in the chain of narration like hanging, mursaland perplexinghadiths or due to intricate defect in the same like deceitful and concealed mursal hadiths. The second section of the chapter addresses weak hadiths due to defects in the integrity of the narrator like forged hadiths, disregarded hadiths, the narration of innovator and the anonymity of the narrator. The third section explores weak hadiths based on the accuracy of the narrator likeanomalous hadiths, the addition in the hadith from trustworthy narrator, interpolated hadiths, disclaimed hadiths, inverted hadiths, mu'alal hadiths, defective hadiths, inconsistent hadiths, dot and vowel-distorted hadiths. Chapter five deals with literature on hadith narrators in terms of method or way of transmitting the narration, forms of transmission and way of performance. The dissertation concluded that Imam Al Salmi was a well-rehearsed and establishedas a scholar in hadith science as evident in his exegesis of Jami Sahin and his other books. He agrees on the definition of the majority of hadith terms; however, the word hadith, according to him, is restricted to verbal tradition not including the deeds or the approval of the prophet.In comparison to traditionists viewpoint, he argued in favour of the jurist viewpoint that acceptance of hadith rests upon the integrity of the narrator even if the chain of narration is interrupted; thus, he accepts interrupted, mursalhadiths, literally transmitted hadiths as well perplexing hadiths under special conditions. He also accepts the narration of reliable innovator if he considers lying is prohibited and the additions from a reliable narrator based on considerable evidence set by jurists.