What are the differences between the 2 Muslim sects Sunni & Shiite ?

EDITED TEXT: I can't believe some of the ignorance revealing itself here. Islam is not evil. Muslims are not evil. A few fanatic crazy people blow themselves up because they've been brainwashed into doing this - this does not represent Islam. I'm brought up Christian - I don't particularly follow any religion to the letter, but attitudes like what I'm reading here, baked in ignorance and marinated in baseless propaganda will only make the current situation worse. Differeing peoples only come together through tolerance and understanding. You mustn't think that all Muslims are intolerant and fanatical because a miniscule fraction capture all the headlines. Smarten up people.

/rant

As to the question...

Sunni:

The Sunni are the largest group in Islam. In Arabic, as-Sunnah literally means principle or path. Sunnis and Shi'a believe that Muhammad is a perfect example to follow, and that they must imitate the words and acts of Muhammad as accurately as possible. Because of this reason, the Hadith in which those words and acts are described are a main pillar of Sunni doctrine.

Sunnis recognize four legal traditions (madhhabs): Maliki, Shafi'i, Hanafi, and Hanbali. All four accept the validity of the others and Muslims choose any one that he/she finds agreeable to his/her ideas. There are also several orthodox theological or philosophical traditions (kalam).

Shi'a:

Shi'a Muslims, the second-largest branch, differ from the Sunni in rejecting the authority of the first three caliphs. They honor different traditions (hadith) and have their own legal traditions. Shi'a scholars have a larger authority than Sunni scholars and have greater room for interpretation. The Imams play a central role in Shi'a doctrine. Shi'a Muslims hold that Muhammad, his daughter Fatima and the twelve descendants of Muhammad, the Imams, were all sinless and pure. This is based on Qur'anic verses (such as 33:33) and Hadith narrations such as the Event of the Cloak.

The Arabic word Shi'a literally translates into the word 'supporters' or 'followers'. Originally known as Shi'at ul Ali (the supporters of Ali), the group formed shortly after the death of Ali, in Iraq. Ali ibn Abi Talib was the cousin of prophet Muhammad, and after marriage to Fatima, he also became Muhammad's son-in-law. Muhammad was raised in the house of Abi Taleb after he became an orphan; therefore he and Ali were raised as brothers.

The Shi'a consist of one major school of thought known as the Ithna 'ashariyah or the "Twelvers", and a few minor schools of thought, as the "Seveners" or the "Fivers" referring to the number of infallible leaders they recognize after the death of prophet Muhammad. The term Shi'a, when used without qualification, is usually taken to be synonymous with the Ithna Ashariyya or Twelvers. Most Shi'a live in Iran, Iraq (the country where Ali died), Bahrain, Lebanon, India, Azerbaijan, Yemen and Pakistan. A minority group (about 10-15 million) of Shi'a is known as Ismaili. The Shia Ismaili branch is subdivided into Nizari Ismaili and Mustaali Bohra subbranches. The Nizari Ismaili or are led by the Aga Khan and are found mainly in Pakistan, Tajikistan, Bangladesh, India, Canada and United States, although the modern day practices of this branch are very different from that of the mainstream Twelvers. The Mustaali Bohra branch is further subdivided into Dawoodi and Sulaimanis subsects. The Dawoodi Bohras are concentrated in Pakistan and India. The Sulaimani Bohras are concentrated in Yemen and Najran province of Saudi Arabia.

shia is similar to catholics in christianity.

sunni: follow the Quran and prophet Muhamamd

Shia: follow the Quran and prophet Muhammad and Ali .

shia add things into Islam that is not necessary in Islam. and they mostly found in Iraq, Iran, and lebanon. and random few numbers in all around the muslims world.

sunni is very detail and has lots of procedures... however the execution is soft and full of diplomatic,

while shiite is less hassle in procedures, straight to the point but they are very strict in execution with less tolerence.

i guess i am right, my personal opinion, pls correct me if i am wrong.

i am with Smiddy on this his answer states evrything in full detail

Hummmm....Evil people and Evil people. They are still all muslims and should both be eliminated. Sorry - not very respectfull.

Well, in my opinion, evil is evil...that's about as much respect as I can show you on this question.