Cathedrals and Churches

Currently, Wikipedia seems to provide the most straightforward introduction to the world of cathedrals and of churches more generally.

Cathedral

"A cathedral (Lat. cathedra, "seat") is a Christian church that contains the seat of a bishop. It is a religious building for worship, specifically of a denomination with an episcopal hierarchy, such as the Roman Catholic, Anglican, Orthodox and some Lutheran churches, which serves as a bishop's seat, and thus as the central church of a diocese ... " more (http://en.wikipedia.org/wiki/Cathedral)

List of cathedrals

"This is a list of cathedrals by country, including both actual cathedrals (seats of bishops in episcopal denominations, such as Catholicism, Anglicanism, and Orthodoxy) and a few prominent churches from non-episcopal denominations commonly referred to as "cathedral", usually having formerly acquired that status ..." more (http://en.wikipedia.org/wiki/List_of_Cathedrals)

Christian Denomination

"A Christian denomination is an identifiable religious body under a common name, structure, and doctrine within Christianity. Worldwide, Christians are divided, often along ethnic and linguistic lines, into separate churches and traditions. Technically, divisions between one group and another are defined by doctrine and church authority. Issues such as the nature of Jesus, the authority of apostolic succession, and papal primacy separate one denomination from another ..." more (http://en.wikipedia.org/wiki/Christian_denomination)

Portal : Anglicanism

" Anglicanism most commonly refers to the beliefs and practices of the Anglican Communion, a world-wide affiliation of Christian Churches. There is no single "Anglican Church" with universal juridical authority, since each national or regional church has full autonomy. As the name suggests, the Anglican Communion is an association of these churches in full communion with the Archbishop of Canterbury. With over seventy seven million members, the Anglican Communion is the third largest communion in the world, after the Roman Catholic Church and the Eastern Orthodox Churches ..."more (http://en.wikipedia.org/wiki/Portal:Anglicanism)

Portal : Eastern Christianity

" Eastern Christianity refers collectively to the traditions developed from first century early Christians in the church headed by Apostle Paul to Byzantium, in what is now the Balkans, the Near East/Middle East, Africa, and Eastern Europe .. ." more (http://en.wikipedia.org/wiki/Portal:Eastern_Christianity)

Roman Catholic Church

"The Roman Catholic Church, more commonly and properly called the Catholic Church (Latin: Ecclesia Catholica), is the world's largest Christian Church representing over half of all Christians and one-sixth of the world's population. Comprising the Latin Rite Western church and twenty-two smaller Eastern Catholic Churches, it is divided into 2,782 sees ..." more (http://en.wikipedia.org/wiki/Roman_Catholic)

The Anglican Domain

The Anglican Domain is a website about the Anglican (Episcopal) Church around the world, produced by the Society of Archbishop Justus . Useful lists of links to official websites for National Churches, Provinces, Dioceses, and Church Publications. See also the weekly magazine  Anglicans Online - whose core is "our comprehensive and up-to-date listing of online resources", one section of which is Music Resources.