Salam. There are different schools in Islam. The main ones are;
Ahl Sunnah (People of Tradition) i.e. sunnis. And it has different theological and jurisprudential schools. Main theological sunni beliefs are, Maturidi and Ashari (There was also Mutazili school but it faded away in time because of the opression on the followers of this school. They were very close shia in beliefs.) And main jurisprudential schools in sunnism are Hanafi, Shafi, Hanbali and Maliki. (It must be noted that there were more than four. It was king Baibars of the Mamluk Dynasty that interfered jurisprudential schools and opened a madrasah/school where four bought scholars taught religion as he liked. Later after Ottomans invaded Egypt, they took this and spread it to the whole world. The accusation of other sects with herecy started then. Especially against shiites, because only shiites question islamic history, especially kings, sheikhs, sultans, etc. of ancient times and today. Thus the Ottoman Sultans and the kings of dynasties would not like this.)
Ahl Tasawwuf, i.e. sufis. (People of Woolen Cloack) (Their signs were the clothes they wore. And wool represented not caring about material things.) They have orders named after the famous sheikhs they follow. i.e. Qadiris, Nakshibandis, Ajzimandis, etc. and beliefs of each one in slight issues might vary from one order to another. And they have a certain lifestyle. However, they don't have different jurisprudential schools. (In ancient times they had. Like the jurisprudential school of Sufyan ath-Thawri. However as stated above, they faded away in time due to the opression on them.) Today's sufis follow either sunni jurisprudential schools or shia ones. The ones following shiite jurisprudential schools are usually referred as Arifan (gnostics), their school is referred as irfan.
Ahl Tashayyu, i.e. shiites [the Partisans (of Ali as a successor after the Prophet)]. And they have different schools also. Imamis (Twelver in beliefs, Jafari in jurisprudential school. This one I emraced with the exception of disagreements on very few theological beliefs and historical matters), Zaydis, Ismailis, etc.
Apart from these three common denominations of Islam, there is also Ahl Hadith, Salafism, Wahabism, Quranism, Ahmadism, etc. A can of worms, eh?
My daughter, I would suggest studying the main beliefs of Islam first. They do not change from one sect to another. And here, I listed some of booklets you might like to read:
http://www.religiousforums.com/foru...tures/153272-invitation-islam-short-book.html (Please ignore the imamah topic in one booklet there as it is related to just shia islam.) Later you can dive into slight differences in faith and jurisprudence and make your mind on every topic (and it is possible that on one issue you might agree on something with a school of thought and it is possible on another issue you might agree with another. You don't have to limit Islam to just one school of thought). And you need to study any faith with the subscribers of that faith. Otherwise, sadly, misinformation/disinformation will always haunt you. The differences cause problems today because people do not know the beliefs of each other well. Otherwise co-existence would be much easier today. I hope I make sense. ma salam