What is Zen?
In Zen Buddhist traditions (but nobody really knows), the first Zen Buddhist was a Brahman man called Bodhidharma. According to these stories, Bodhidharma came to China from India about 425 AD. Possibly Bodhidharma was fleeing the Guptan kings, who were Hindus and not Buddhists.
The main point of Zen Buddhism was that people should learn from direct experience and not from being told facts or having ideas explained to them. The best way to find out why you should meditate was to meditate. The best way to appreciate a flower was to look at a flower, not to study about flowers.
In one story about Bodhidharma, Bodhidharma met with Emperor Wu of the kingdom of Liang. Emperor Wu asked Bodhidharma what he had gotten out of all the money Emperor Wu had given to the Buddhists. Bodhidharma replied "Nothing at all." The Emperor asked "Then what is the truth of the teachings?" Bodhidharma replied, "Vast emptiness, nothing holy." So the emperor asked "Then who are you standing in front of me?" Bodhidharma replied "I don't know," and walked out. This story shows how Zen masters refused to explain their ideas in words.