In terms of world size the Orthodox Church ranks next to the Roman Catholic Church. In England there are about 250,000 people in the Greek Archdiocese, 100,000 in the Serbian Diocese, and 5,000 in the Russian Archdiocese. There is now an Orthodox Christian presence in every major town or city in England. Increasingly you will find English used alongside the mother tongue and in most congregations there will be people who were not originally Orthodox in faith.
Today it is often difficult to see any difference in the interiors of Catholic and Protestant churches, but an Orthodox building and its worship will be very distinctive. The altar area will be enclosed by a large screen full of icons and the walls will be covered with further icons of the saints with lamps in front of them. The singing will be unaccompanied and normally reserved for trained cantors.
The worship will be bathed in incense and surrounded with colour. Even the Holy Gospel Book is bound in golden covers with elaborate symbols. The Orthodox Churches have had no Reformation, Counter-Reformation, or Vatican 2. There has been a quiet development from the time of the apostles until the present age without any major breaks. The Greek Orthodox Church preserves and reads the New Testament in the original Greek in which it was written, even when it is translated immediately afterwards. It honours the Greek Septuagint version of the Old Testament which pre-dates the Massoretic Hebrew text followed by Protestants.
The Orthodox Church has no central HQ like the Vatican. Its bishops meet in worship and in synods, but do not need have any permanent secretariat. Orthodox Christians outside Eastern Europe, Asia, and Africa are served by bishops who are members of one of these self-governing churches. Constantinople, Antioch, Moscow, and Serbia all have large numbers of Christians outside their home areas.