Answer) Al Quran is Qata’i al Thabut and Sunnah is Dhanni al Thabut and it is ‘Usool that preoity is given to Qata’i over Dhanni .The detail is as below : The Khabar that reached to us from Prophet SAW with sahi sanad is considered as Maqbul (acceptable/reliable).The sound sanad (chain of narrators of the Hadith ) is that the narrators from first narrator to Prophet SAW are mentally sound, religiously reliable and having powerful memory and the same chain does not breaks down in the chain . For example Imam Malik narrated from Abi Az Zanaad ,Abi Az Zanad from ‘Araj and ‘Araj from Abi Hurrairah and Abi Hurrarah from Rasulullah SAW. In this chain all the three persons are reliable as per the ‘isnad Criteria.So this Sanad will be called sound sanad and this Hadith is called Marfu’.If this sand reaches upto suhabi this is called mawquf ,If it reaches upto tabi’ee and the Suhabi is missing we call this chain as maqtu’ as chain breaks down and fails to reach to Prophet SAW through Suhabi.If the same chain reaches to Prophet SAW then it is categorized as Muttasil.If any of the narrators of this hadith is not trustworthy and completely competent person ,either in his ability to memorise or to preserve what he wrote then the same Mttasil hadith is termed as muttasil Za’eef. In the same pattern hadith is deemed as acceptable if its narrators are reliable. In the hadith collections Bukhari is considered the most shahih collection and thereafter comes the number of Muslim Sharief .keeping the principles of Hadith in view there are many kinds in ahadith which has been defined by the muhadithun in ‘usool al Hadith. Hadith which has only on sanad is called a Gharib and which has two isnad is called Aziz ;for instance a hadith is narrated by Imam Malik through the above mentioned chain is also narrated by him through this chain: Imam Malik from Nafi’,Nafi’ from Abdullah Ibn Umar (Suhabi)and Abdullah ibn Umar from Nabi SAW. hadith having more than two narrators is termed as Mashoor.All these three types are categorised as Aahaad. A successive narration (mutawatir) is one conveyed by narrators so numerous that it is not conceivable that they have agreed upon an untruth thus being accepted as unquestionable in its veracity. The specific mutawatir hadith is considered as Qat’i al thubut as compared to Aziz and Gharib because there is sort of sepeculation in them. There are a few ahadith which are successive (mutawatir) in nature and rest of ahadith are falling in other catogaries like Ahaad Etc.but so for Quran is considered its every word has come to us through tawatur therefore is given priority over hadith .Both the meaning and word of Quran is Qata’i while as the meaning of Hadith is considered Qatai’Ii while as its words are Dhanniin nature. (Note)Due to the significance of this question we opted to translate the full text on this topic from Aqaid Al Islam by Abdu Haq Haqqani RA rather than providing a brief summary of these terms.