Our tradidion is more than 2500 years old and has been founded by the ancient Buddha, Siddharta Gautama Shakya, the prince who became an asketic. His Dharma has been memorably transmitted to Mahakashyapa:
One day Buddha gave a Dharma talk on the crag of Vulture. He was sitting on a rock for a long-long time silently. The students started to become a bit inpatient and thought something is not ok. Finally Buddha held up a flower and showed it to them.
Nobody understood him. Only Mahakashyapa was smiling. When Budhha saw him he said:
"I owe the eye of the true Dharma, the Formless Form, the gate of the highest Nirvana, that I am transmitting now to Mahakashyapa."
This action was the first Dharma transmission of our age, the beginning of zen teaching.
This transmission is not something msytic, abstrack action, but the Dharma, the realisation of the enlighenment from the student and its verification by the teacher. Those who are given the Dharma this way has all realised the same: their True Nature, the substance without name and form.
That's how buddhist tradition was born. Later buddhist teachings were taken to China by Bodhidharma where zen tradition has started as a special mixture of buddhist and taoist teachings. Bodhidharma was the irst patriarch of zen.
Zen Master Seung Sahn, the founder of Kwanum School of zen, was the 78th Patriarch of above mentioned tradition.