Having acquired this basic skill, the Yogi proceeds to expand his practice by taking on the more complex objects of meditation chants, colorful religious images, energy channels in the body and so forth. Still, no matter how complex the object of meditation, the meditation itself remains purely an exercise in concentration. Within the Buddhist tradition, concentration is also highly valued. But a new element is added and more highly stressed. That element is awareness.
All Buddhist meditation aims at the development of awareness, using concentration as a tool.
The Buddhist tradition is very wide, however, and there are several diverse routes to this goal. Zen meditation uses two separate tacks. The first is the direct plunge into awareness by sheer force of will. You sit down and you just sit, meaning that you toss out of your mind everything except pure awareness of sitting. This sounds very simple.