The terms Sunyata (or Shunyata), void and emptiness are synonyms in Buddhist philosophy. They are ways of expressing the sense that all we see, feel and observe is relative, in fact non-essential and not self-sustaining. This insight is called prajna paramita. To find the essential, that is the challenge that Tibetan Buddhism offers us. One clue can be given: compassion, insight and calmness in the mind are part of the essence of things.