Sahih Hadith (, ) in Hadith terminology, may be translated as "" or "sound hadith (prophetic narration)". Ibn Hajar defines a hadith that is ' ("á¹£aḥëḥ in and of itself") as a singular narration (ahaad; see below) conveyed by a trustworthy, completely competent person, either in his ability to memorize or to preserve what he wrote, with a muttaá¹£il ("connected") isnÃÂd ("chain of narration") that contains neither a serious concealed flaw (ûillah, Arabic:ùÃÂé) nor irregularity (shÃÂdhdh). He then defines a hadith that is á¹£aḥëḥ lighairihi ("á¹£aḥëḥ due to external factors") as a hadith "with something, such as numerous chains of narration, strengthening it." In the Sunni branch of Islam, the canonical hadith collections are the six books (Kutub al-Sittah) listed below.
Ibn Hajar's definitions indicate that there are five conditions to be met for a particular hadith to be considered á¹£aḥëḥ:
A number of books were authored in which the author stipulated the inclusion of á¹£aḥëḥ hadith alone.
Ḥasan ( meaning "good") is used to describe hadith whose authenticity is not as well-established as that of á¹£aḥëḥ hadith, but sufficient for use as supporting evidence.
Ibn Hajar defines a hadith that is ḥasan lithatihi"ḥasan in and of itself"with the same definition a á¹£aḥëḥ hadith except that the competence of one of its narrators is less than complete; while a hadith that is ḥasan ligharihi ("ḥasan due to external factors") is determined to be ḥasan due to corroborating factors such as numerous chains of narration. He states that it is then comparable to a á¹£aḥëḥ hadith in its religious authority. A ḥasan hadith may rise to the level of being á¹£aḥëḥ if it is supported by numerous isnÃÂd (chains of narration); in this case that hadith would be ḥasan lithatihi ("ḥasan in and of itself") but, once coupled with other supporting chains, becomes á¹£aḥëḥ ligharihi ("á¹£aḥëḥ due to external factors").
According to Sunni Islam, which reflects the beliefs followed by 80âÂÂ90% of adherents of Islam worldwide, Sahih status was achieved by the first two books in the following list (known as "the six books" or Kutub al-Sittah):
Different branches of Islam refer to different collections of hadiths or give preference to different ones.