Why are there so many denominations in christianty?

One of the differences is first in the bible of Roman Catholic we have a deutrocanonica which is I called the "middle bible" it has the scriptures in between the old books and the new books (which is when Jesus was born). Other denomination doesnt have this. Another one is that Roman Catholic is a uniform church, meaning that the everywhere you go in whichever country, whichever language, whatever tradition, the church service would always be the same. The main "office" is only one which is in Rome and the pope is the leader. They have network of data as well so everything is connected. Say like for example, even if you move around and such, the church will always have your data as in when and where you were baptized, the sacrament that you have received, whether you have been married and where etc2 :) so its all connected. As for the reason why there are so many denomination? I guess although we study from the same bible (the main part of the bible is the same for Catholic and Christian) people have different way of intepreting them. Or sometimes within a church people have problem with their fellow christian, and decided to separate and make another church and all those stuff.