Some of schools of thought and deviant sects or groups.

Shi'ah & the Rafidah
  1. Isma'iliyah
  2. Dawudi Bohras
  3. Qarmatians
    An offshoot of Isma'iliyah
  4. Zaydiyah
  5. Imamiyah (Ithna ‘Ashariyah)
  6. Shaykhiyyah
  7. Babism
    An offshoot of Shi'ah & Sufi
  8. Baha'ism
    An offshoot of Shi'ah & Sufi
  9. Ghulat Shi'ah
  10. Ghurabiyah
  11. Jafari
  12. Druze
  13. Yazidi
  14. Nusayriyah (Alawites)
Sufism
  1. Jama'at At-Tabligh
    Founded by Muhammad Ilyas, a grave-worshipper Sufi.
  2. Deobandiyah
  3. Barelwiyah
    An offshoot of Sufi & Qadianism.
  4. Naqshabandiyah
  5. Qadiriyah
  6. Sadhiliyah
  7. Chisthiyah
  8. Ahmadiyah (Qadianiyah, Qadianism)
  9. Mawlawiyah (Whirling Dervishes)
  10. Rifa'iyah
  11. Tijaniyah
  12. Khalwatiyah
  13. Burhaniyah
  14. Khidriyyah
  15. Khatmiyah
  16. Ja'fariyah
  17. Alawi (Morocco)
  18. Ahmadiyah
  19. Agamiyah
  20. Badawiyah
  21. Dasuqiyah
  22. Harbiyah
  23. Fatimiyah Sufi Order
  24. Al-Amudiyyah (Sa’id bin ‘Isa Al-Amudi, Hadramout Yemen)
  25. Bektashi Order
  26. Ahmadiyyah-Idrissiyyah
  27. Abbasiyyah
  28. Akmaliyyah (Haqmaliyyah)
  29. Azimia Sufi Order
  30. Tariqa Alawiyya
Khawarij
  1. Ibadiyah
  2. Haruriyyah
Quranism (Sunnah/Hadith Rejectors)
  1. Tolu-e-Islam
    Initiated by Ghulam Ahmed Pervez in Pakistan.
  2. Submiiters/Submission
    Founded by Rashad Khalifa in the US.
  3. Quran Sunnat Society
    The movement was behind the first-ever woman to lead mixed-gender congregational prayers in India.
  4. Kala Kato
    Nigerian group
  5. Malaysian Quranic Society
    Founded by Kassim Ahmad.
  6. Zumratul Jamiu Mumin
    Movement in Nigeria.
  7. Izgi Amal
    Its leader Aslbek Musin in Kazakhstan.
  8. Ahle Quran
    Formed by Abdullah Chakralawi in Pakistan.

Al-Kalam (theological rhetoric)
  1. Ash'aris
  2. Maturidis
  3. Murji'ah
  4. Jabariyyah
  5. Mu'tazilah
  6. Qadariyah
  7. Jahmiyyah
    The Jahmis deny the divine attributes and say that the Qur’an was created, that Allah will not be seen in the Hereafter, that Muhammad was not taken up to Allah (on the night of the Mi’raj), and that Allah has no knowledge, power or life, and so on, as the Mu’tazilah, philosophers and their followers said.

Others
  1. Al-Ikhwan Al-Muslimun
    Hasan Al-Banna was the founder of this group and he was a Sufi.
  2. Nation Of Islam (Farakkanism)
  3. Al-Karamiyah
  4. Al-Salimah
  5. The Qutubis
  6. Sururiyah
  7. Ba'ath Party
  8. Ahbash (Habashi)
    This sect spreads the doctrine of the Jahmiyyah who deny the names and attributes of Allah, as well as the doctrine of the Jabariyyah concerning destiny. It also calls to some Sufi and Batini (esoteric) beliefs

Islam enjoined all people to unite on that and cast away anything that may lead to conflict and division, and it emphatically forbade splitting and differing from one another. Allah Ta'ala says: “and be not of Al‑Mushrikun (the polytheists, idolaters, disbelievers in the Oneness of Allah). Of those who split up their religion (i.e. who left the true Islamic Monotheism), and became sects, [i.e. they invented new things in the religion (Bid‘ah), and followed their vain desires], each sect rejoicing in that which is with it.” [Al-Rum :31-32, with tafsir Al-Qurtubi 14/32], and it was narrated from Ibn Mas‘ud that the Prophet ﷺ said: “Do not differ, for verily those who came before you differed and thus they were doomed.” [Narrated by Al-Bukhaari (3476)]. It is not Islam that is divided into sects that differ from one another and oppose one another; rather it is the people who differ according to how far away they are from the religion and the extent to which they have abandoned the Sunnah of their Prophet and followed their desires. It was narrated Ibn Majah (3992) and Ibn Abi ‘Asim in Al-Sunnah (53) that ‘Awf ibn Malik Al-Ashja‘i (may Allah be pleased with him) said: The Messenger of Allah ﷺ said: “The Jews split into seventy-one sects, one of which will be in Paradise and seventy in Hell. The Christians split into seventy-two sects, seventy-one of which will be in Hell and one in Paradise. By the One in Whose hand is my soul, my ummah will split into seventy-three sects, one of which will be in Paradise and seventy-two in Hell.” It was said: O Messenger of Allah, who are they? He said: “The jama’ah (the main body of the Muslims).” [Classed as sahih by Al-Albani in Al-Sahihah 1492] and according to another hadith: “The path on which I and my Companions are.” [Narrated and classed as sahih by Al-Tirmidhi 2641].

Imam Ibn Al-Mubarak (may Allah have mercy on him) said: "The roots of the seventy-two sects are four: the Khawarij, the Rafidah (Shi'ah), the Qadariyah and the Murji’ah." It was said to Ibn Al-Mubarak, "And the Jahmiyyah?" he (may Allah have mercy on him) said, "the Jahmiyyah are not part of the ummah of Muhammad ﷺ." [Quoted by Shaykhul Islam Ibn Taymiyyah in his book: Majmu’ Al-Fatawa 35/414]