Meditation is an act that is as human as to breathe. We all meditate, perhaps in different forms, but the act of meditating is normal, natural and unavoidable, whether it arises through unconscious effort, analysis of a problem, or simple rest. However, just as any human action, it can be directed and improved, so that as a technique we achieve better results and a clearer direction, or have more ways to release tension or response to stressful circumstances. To delve further into this topic we must consider some mysteries: What do we mean by meditation or relaxation? What is their philosophical and scientific basis? What principles can help us understand the reality in which we find ourselves? And, finally, what are some techniques and fundamental practices in which we can train ourselves without having to take vows as a monk or become a hermit?