The khabar (report) which is synonymous with the terms hadīth and Sunnah, in terms of the line of transmission is divided into the khabar mutawatir (continuously recurrent report) and khabar ahad (isolated report). The mutawatir comprises of four issues, they are:

1. The number of transmitters should be such that they are a group and not be restricted to any specific number. So whatever number proves to be a group is considered mutawatir provided it fulfills the other conditions. 2. It should preclude the collusion on a lie, this differs according to the difference of persons and places, so five people like 'Ali ibn Abi Talib are sufficient to consider a report as mutawatir. Probably with other people five may not be sufficient. Five transmitters who have not met from five different lands may be enough for the report to be considered as mutawatir because they did not meet in one place so as to collude. Probably a report (khabr) by the same number of people in one land may not suffice.

3. That they transmit the report from a group like them from the beginning to the end of the transmission, in a manner that precludes collusion on a possible lie, even if they were not of the same number. In other words, the first two conditions should be met in every tier of transmitters.

4. The basis of their conclusion should be sense perception, by hearing and other such senses and not what the pure reason establishes because it can make mistakes if it is not based on sense perception. Therefore it does not amount to certainty. The rule (hukm) of the mutawatir report is that it yields positive knowledge ('ilm daruri). It is what one is compelled to accept such that he is unable to confute it. It is indispensable because it does not require study i.e, the the mutawatir report imparts certainty (yaqin). The mutawatir report is divided into two categories: verbal (lafzan) mutawatir like the hadīth:

“Whosoever intentionally lies about me, let him reserve his place in the Hellfire” [Reported by Muslim on behalf of Abu Hurairah ] And the hadīth of wiping on the leather socks, hadīth of hawd (river in paradise), hadīth of intercession (shafa'a) and the hadīth of raising the hands (raf' al-yadayn) in prayer. The mutawatir by meaning (ma'na) is when the transmitters concur on a matter occurring in difference incidents such as the Sunnah of the morning prayer (Fajr) being two rakats. It does exist. Numerous mutawatir ahadīth have been reported even though the '‘Ulamā differ on what constitutes mutawatir according to their different views about the mutawatir report.

As for the Isolated report (khabar al-ahad), it is the report whose narrators have not reached the number required for the mutawatir, whether it was reported by one or four narrators i.e, it is the report which falls short of the preceding four conditions mentioned for the mutawatir report. It is categorised in terms of the number of narrators, into three categories:

1. Gharib (alien): it is the report narrated by a single transmitter i.e, there is a single narrator throughout the narration at a stage in the isnād. It is divided into: gharib in isnād only, and gharib in isnād and matn together. There is nothing called gharib in matn only. The gharib in matn and isnād is the narration by a single narrator, such as the hadīth prohibiting the sale of wala (patronage) and its gifts. The gharib in isnād and not in matn is the matn which has been narrated by a group of Sahabah but a transmitter has a single narration from another Sahabi like the hadīth:

2. Aziz (scarce): It is a report transmitted by more than one narrator but less than four i.e, what two or three narrators have transmitted even if they are of the same rank, it is called aziz (scarce) due to its rarity.

3. Mashhur (famous): A report which has been narrated by more than three narrators but did not reach the level of mutawatir. It is called mashhur due to it being clear and widely mentioned amongst the people whether a sanad (chain) was found for it or was not found originally. It is also the mustafid (comprehensive). It has two categories: mashhur according to the scholars of hadīth and mashhur for the general public. The first is like the hadīth of Anas:

And the second category is like the hadīth:

Not every mashhur report among people is Sahih. Certain hadīth may become famous amongst people which do not have any basis or are entirely fabricated. There are many, .like the hadīth:

It is baseless. The Khabar al-ahad also, whether it is gharib, aziz or mashhur, its isnād has a termination point; either it ends with the Prophet  or with a Sahābi or tabi'i. In terms of the end of the chain there are three types:

1.Marfu': It is a report which has been specifically ascribed to the Prophet  in terms of his action, saying, consent or attribute, whether the one who attributed it to the Prophet  was a Sahābi, tabi'i or someone after them. Included in this is when the Sahābi says:

Or

Or

Or

Or

Or

Included in this is also when the Sahābi says:

Or

From the marfu' report is also when the Sahābi says:

Even if they did not attribute it to the Prophet  because this indicates a consent. Similarly, the saying of Anas ibn Malik is considered as a marfu' report when he said:

And when Anas said ;

Similarly the tafsīr of the Sahabah concerning the cause of revelation comes under the rule of the marfu' report. Anything other than that from the tafsīr of the Sahabah is not considered part of the hadīth. This is because the Sahabah performed many Ijtihāds in explaining the Qur’ān and they disagreed as a result. Also we find many of them used to narrate israiliyyat from the people of the Book. That is why their tafsīr is not considered part of the hadīth let alone be considered as a marfu' hadīth.

2. Mawqūf: It is the narration from the Sahabah in terms of their saying and action, its application is specific to the Sahābi. Its isnād can be continuous or broken. It is the report many of the Fuqaha and muhaddithun also call athar. The mawqūf does not establish a proof (hujjah) because Allah  said:

The understanding is: whatever is brought to you from other than the Messenger  do not take it. Therefore, it is not a proof (hujjah) for anyone except when it is from the Messenger of Allah . It is not permitted to ascribe it to the Messenger of Allah  because it is a mere possibility and not a preponderant opinion (zann) and possibilities are not recognised.

3. Maqtu': It is not the same as munqati'. The chain stops at the Tabi'i; in terms of his saying and action. A proof is not established by it and it is weaker than the mawqūf.