The practice of Yoga can best be introduced by quoting "The Sivananda Companion to Yoga," by The Sivananda Yoga Center:
"Anyone can practice yoga. You don't need special equipment or clothes - just a small amount of space and a strong desire for a healthier, more fulfilled life. The yoga postures, or asanas, exercise every part of the body, stretching and toning the muscles and joints, the spine, and the entire skeletal system. And they work not only on the body's frame, but on the internal organs, glands, and nerves, keeping all systems in radiant health. By releasing physical and mental tension, they also liberate vast resources of energy. The yogic breathing exercises known as pranayama revitalize the body and help to control the mind, leaving you feeling calm and refreshed, while the practice of positive thinking and meditation gives increased clarity, mental power, and concentration."