Zazen

Zazen is a form of seated meditation that is central to Zen Buddhism. The practice is austere and, therefore, sometimes difficult for beginners to engage in. The effects of Zazen accumulate over time and result in a qualitative difference in subjective experience.

My own Zazen practice follows a 25-minute seated meditation, followed by a 5-minute walking meditation.

During the 25 minutes, practitioners sit in a comfortable posture and perform one of several different practices. Koan practice, breath meditation, and Shikantaza are the three main forms of meditation during Zazen that I am aware of, although I suspect that there may be others. MeditationBodyPosture is also an important topic. I personally sit Seiza style. Full lotus, half lotus, and simply sitting in a chair are also popular postures.

The 5-minute walking meditation is done mainly to relieve the body of any pain or discomfort, and give the meditator a chance to stretch their legs. The walking meditation, called Kinhin, is supposed to be done with a meditative attitude, although many meditators often perceive a qualitative difference between Zazen and Kinhin. (And of course they would -- walking and sitting have very different flavours).