Shia / Sunni

Who are the Shia, who are the Sunni and why do they hate each other so much that they butcher each other seemingly in the name of the Quran.
Mohamed was a prophet for Islam, much in the way Abraham was to the Jews and Christ was to the Christians.
The problems arose when it came to the succession of Mohamed in 632 AD and the split between Shia, who chose a member of Mohameds blood line, his cousin Ali and the Sunni who chose an elected person according to tribal custom. The term Sunni derives from Ahl-a-Sunnah, meaning people of tradition which denotes the traditional approach to appointing a successor to Mohammed whilst Shia is derived from Shiat Ali, meaning the party of Ali. 
The Sunni Muslims appointed a 'Caliph' as leader who importantly was considered 'just a man' there to maintain law and order, whilst the Shia appointed an 'Imam' who was considered infallible.
In an attempt to unite the two factions Ali was also proclaimed the 4th Caliph bringing both schools of belief together.  On Ali's death, Ali's son, Hussein was not appointed Caliph under the Sunnis, despite being the rightful heir under the Shia and Hussein's death at the hands of the Sunni Umayyad family, in the battle of Karbala, made him a martyr for the Shia cause.
The rest as they say is history but what a bloody history it continues to be. It almost beggars belief that these events 1500 years ago still create the fervour, the passion for so much enmity, such feelings of vengeance.
Its perhaps one of the inherent problems of 'faith', Problems become nearly unresolvable because of the intensity of belief which in its self excludes compromise, there is no right and wrong, only them and us !!!  

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