Zen is a type of Buddhism that began in China and flourished in Japan. Practicing Zen Buddhism includes meditating while observing the flow of your breath in and out.
Zen is the Japanese pronunciation of a Chinese word, ch'an, which comes from a Sanskrit root meaning "thought," "absorption," or "meditation." And meditation is at the heart of Zen, along with an emphasis on self-control and insight. Most Zen Buddhists have a teacher they look to for wisdom and guidance as they practice.