Hadith root of why there is no single "fiqh" system, but rather a collection of parallel systems within Islam. Much of early Islamic history available today is also based on the hadith, although it has been challenged for its lack of basis in primary source material and the internal contradictions of the secondary material available. Hadith may be "hadith qudsi" (sacred hadith) — which some Muslims regard as the words of God (Arabic: Allah) — or "hadith sharif" (noble hadith), which are Muhammad's own utterances. According to as-Sayyid ash-Sharif al-Jurjani, the hadith qudsi differ from the Quran in that the former
Introduction to the Science of Hadith well known as of late as: "Muqaddimah Ibn al-Ṣalāḥ fi `Ulūm al-Ḥadīth", "Ibn al-Ṣalāḥ's Introduction to the Sciences of Hadith". Nūr al-Dīn `Itr, in the introduction to his edition of the "Introduction", concluded that its actual name is either "ʻUlūm al-Ḥadīth" ("The Sciences of Hadith") or "Ma`rifah Anwā`i `Ilm al-Ḥadīth" ("Familiarity with the Types of the Science of Hadith"). This is based upon the author's own usage in his own introduction in addition to the usage of other scholars in the centuries after the authoring of the book. Similar to Bint `Abd al-Raḥmān, he acknowledged that the book is most