The Pali word Kammatthana means meditational exercise.

Vipassana is a Pali word which means: Seeing clearly, seeing specially or seeing through (Vi - clearly, specially, into, through + passana - seeing). Vipassana means introspection, intuitive wisdom, intuitive knowledge. Vipassana is often translated as insight.

Seeing what clearly? Insight into what?

Vipassana means seeing through the true nature of reality or Insight into the true nature of reality. It means seeing things as they truely are. Vipassana is the direct and intuitive understanding of the true nature of all mental and physical phenomena.

Vipassana is based on the Four Satipatthana, the Four Foundations of Mindfulness. That is to say, Insight is realized by the consistent and progressive application of the Four Foundations of Mindfulness.

The Four Foundations of Mindfulness are:

1. Mindfulness of the Body,
2. Mindfulness of Feelings,
3. Mindfulness of the Mind, and
4. Mindfulness of the Mind Objects.

-- Taken from "The Only Way," by Venerable Ajahn Tong Sirimangalo, translated by Kathryn Johnston Chindaporn and published in Chomtong, Chiangmai, Thailand, 1999.