The earliest teachings can be traced back to the insights the Buddha received after he gave up the extremes of worldly pleasure and deprivation. He was awakened to the truth of our human condition and spent the rest of his life teaching men and women how to minimize their suffering and difficulties and lead a beneficial life.
His disciples recognized the importance of these teachings and memorized the hundreds of sermons the Buddha gave during his lifetime. Later they were written down and translated.
Commentaries were composed and all these writings form the basis of the Buddhist traditions that continue today. There are several schools of Buddhism, each with its own rituals, forms, and scriptures -- Chan, Tibetan Buddhism, Insight Meditation, Pure Land, and Zen are some of the better known.
Some put greater emphasis on meditation, or on chanting the scriptures, or on certain rituals, but all of them include the core teachings of the Buddha.
As Buddhism was introduced to new cultures it changed and adapted, often taking on some the characteristics those cultures. In this way the teachings spread to China and other parts of Asia.
In the last century or so, Buddhism has taken root in the North and South America, Europe and other countries around the world. Some new forms, rituals, and styles of practice are developing alongside traditions that have been practiced for thousands of years.
How should these teachings be applied to the challenges facing all of us now in this rapidly changing world? How do we best respond to these changes and dangers, in order to live our lives with dignity and be of benefit to ourselves and others? Those who are now practicing with these ancient teachings are answering these questions and the evolution of Buddhism continues.