On the cushion there are countless meditation techniques. Each begins with shamatha. Some will combine shamatha and vipashyana.
Said without Sanskrit terms: All meditation sessions will begin with something pertaining to, eliciting, or in support of centeredness, tranquility of mind and emotions, peaceful attentiveness, spacious clarity, alert impartial focus, attentiveness – subjectively, objectively or both. These are aspects of shamatha therefore of its training.
Vipashyana is an openness to perceive subjective and seemingly objective phenomena less and less through one’s habits of consciousness. The perception of all beings is subjective. Objectivity is questionable due to this. For example, a glass of spring water is perceived as a drink by the average person. If a gold fish were in that same glass and water, it no longer is a drink or drinkable to the average person. Assuming that the pH is appropriate for the gold fish, the fish considers the water and glass as its home. If someone were to pour the glass of spring water into a clean toilet bowl, the average person would not consider scooping the water out and drinking it. From an “objective” perspective, the water is the same in each case but human perception of it changes due to circumstances due to habituated patterns of consciousness. Vipashyana is to learn to remain in an open state of awareness such that habits of consciousness decrease which ensures that conditioned perceptions do, too. This process then becomes a feedback loop such that as patterned consciousness is less relied upon and perception opens.