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There are many branches and sub-divisions of christianity - a whole taxonomy!
One of the best established is Roman Catholicism, aka the Church of Rome. The head of the Roman Catholic (RC) church is the pope.
Anglicanism is also, technically, a "catholic" religion; but it split from the RC church in the time of Henry the Eighth.
Protestant churches are churches that have split off from the RC church; some of them (like the Anglican church) technically "catholic"; others not.
Many other types of christian church/philosophy exist, including - methodism, Calvinism...
"Christian Science doctrine does not forbid medical care, many Christian Science parents claim religious exemption from childhood vaccination requirements. Vaccination is accepted by some members, particularly when the consequences of illness are considered less acceptable." (quote from MMWR)