The Bible says that the Christian church is all of the people who believe in Christianity. According to the Bible it's not a building at all!

But to many people, however, a church is a building where people gather for the worship of God through His son, Jesus Christ.

Church buildings have changed a lot down the centuries.

The first Christians used their own homes as churches. But when they set out to preach the Good News, they had no buildings to use. So they often put up a stone or wooden cross on the site of pagan temples and preached in the open air.