In the field of Hadith Studies, " Science of Critical investigation of Hadith Narrators & quot; is considered highly significant. It is mainly because the objective of this science is to preserve the Prophetic traditions accurately. Muslim scholars are unanimous over the principle that "no information is to be accepted as true except that through the one known as just and honest & quot;, as & quot; testimony is not accepted except of the just and honest & quot;. It is this reason that knowledge about the sources of information (narrators of Prophetic traditions) was deemed necessary. The precise preservation of Prophetic traditions necessitated availability of information about who among the reporters are weak in memory or liars; and also about who among the reporters are well-known for his retentive memory and integrity of character. It shows that special attention was paid to the narrators of hadith with a view to authenticating the reports concerning the Prophet (s.a.w.) sayings and doings. That is why many scholars of hadith lay extraordinary emphasis on chain of narrators (isnad), declaring that focus on the chain of narrators is one of the unique features of Muslim Ummah.