When did the New Testament officially begin and what significance does this starting point hold in the context of Christian history?

The New Testament officially began around the 1st century AD, after the death and resurrection of Jesus Christ. This starting point is significant in Christian history because it marks the beginning of the teachings and writings that form the foundation of the Christian faith. The New Testament contains accounts of Jesus' life, teachings, and the early Christian church, shaping the beliefs and practices of Christians for centuries to come.