(1) Hadith and Sunnah:

In the religious literature of Islam these two terms are considered to be synonymous with each other. There is, however, a slight difference in them. The word Sunnah means precedent and custom. In the technical sense it implies the doings and practices of Muhammad (may peace be upon him) only. Sunnah is thus a concrete implementation, a tangible form and the actual embodiment of the Will of Allah in the form of Muhammad's deeds.

Hadith literally means a piece of news, a tale, a story or a report relating to a present or past event. In the technical sense it stands for the report of the words and deeds, approval or disapproval of the Holy Prophet (may peace be upon him).

(2) Classification of Ahadith:

(a) Sahih (Sound). This name is given to the absolutely faultless hadith, in which there is no weakness either in the chain of transmission (Isnad) or in the text (Matn) and in which there is no tendency to contradict any established doctrine of Islam.

(b) Hasan (Approved) is like a Sahih tradition except for the fact that some of its narrators are found to have a defective memory in comparison to the narrators of Sahih Hadith.

(c) Da'if tradition is that in which there is some defect either in the chain of transmission, or in the proper understanding of the transmitter, or its contents are not in perfect agreement with Islamic beliefs and practices. It is in fact a tradition of weak or less reliable authority.

(d) Mutawatir (Continuous) is a tradition reported by a large number of people in different times, so as to make it impossible for any falsehood to creep into it.

(e) Mashhur is a tradition which is handed down by at least three different reliable authorities, or, according to another view, a tradition which, although widely disseminated later, was originally transmitted by one person in the first generation.

(f) Maudu' (Forged) hadith is that which a liar fabricates and then attributes it to the Holy Prophet (may peace be upon him).

(g) Muttafaq 'Alaih (Agreed upon). A tradition accepted both by Imam Bukhari and Imam Muslim and included in their respective collections.