OM

Picture of the Perseid Meteor Shower by Michael Seeley. https://www.flickr.com/photos/mseeley1/28860028781

What is this sound? 'OM' is universally recognized as an intrinsic part of the practice of Yoga. What is it? The last several sutras have been leading up to the actual expression of the vibration that comes close to encompassing all and everything, past-present-future. Anything you can imagine and everything you have experienced- the fullness of the Universe itself.