Ujjayi breath is often known as Victorious breath. It is most often used with the practice of vinyasa (breath-synchronised movement). Ujjayi means “to conquer” or “to be victorious”.
Ujjayi breath is highly beneficial as it concentrates and directs the breath, giving asana practice extra power and focus. It also helps quiet the mind and slows and smooths the flow of breath. The breath slightly constricts the back of the throat, the glottis. You can imagine fogging up a pair of glasses, where the breath is like a sigh – that is the type of breath Ujjayi is. This constriction of the glottis is done on the inhale and exhale and it creates an ocean like sound (some also describe it as a Darth Vadar sound). It takes some practice to control the throat on both the inhale and exhale and once this is achieved, you can gently close the lips and breath through the nose. This is Ujjayi breath. Although the nose does the breathing, the Ujjayi breath is often called the ocean breath because as the air is inhaled, it passes through the throat.
Try to even out the inhale and exhale in Ujjayi breath to help focus on awareness and prevent the mind from wandering. Ujjayi also assists in creating heat in the body which is said to release toxins from the body and mind. It also provides more resistance during your asana practice.
The breath should be louder than your internal dialogue and loud enough for your neighbour to hear. This helps keep the mind aware of the present moment and also allows the yogi to change from one asana to the next with ease and grace.
This video can be useful to help develop this practice of Ujjayi.
Yoga is the practice of quieting the mind. ~Patanjali (translated from Sanskrit)