In addition to the term 'mantra,' you will also hear the word Naad in connection with Kundalini Yoga mantras. Naad means “the essence of all sound.” It is a particular vibration, a fundamental frequency that comes from one common source or sound current. It is the universal code behind language and therefore behind human communication. 

Naad is the glue or medium that connects the little me, the individual, to the Big Me, the Universal Self. It is the vibrational harmony through which the Infinite can be experienced. 

Naad Yoga is based on the experience of how sound vibrations affect the body, mind, and spirit through the movementof the tongue, the mouth, and changes in the chemicals in the brain.

We can alter consciousness by changing the chemical composition of the fluids in the brain. There are eighty-four meridian points on the upper palate of a human’s mouth. One can feel the upper palate with the tongue and experience its different surfaces. There are two rows of meridian points on the upper palate and on the gum behind the upper teeth.

The tongue stimulates those meridian points, and they in turn stimulate the hypothalamus which makes the pineal gland radiate. When the pineal radiates, it creates a pulse in the pituitary gland. When this happens to the pituitary, the entire glandular system secretes. Then the chemical composition of the brain becomes balanced, automatically changing one’s outlook on life. 

The state of mind, personality, and power to project from our authentic self is tied in with the use of our word.

"If your words have the strength of the Infinite in them and are virtuous, and you value them, you are the greatest of the great. If you do not value your words, you have no value. Your own word is your value as a human being."
-The Teachings of Yogi Bhajan