What is "matsyendranath"

Matsyendranātha, Macchindranāth or Mīnanātha (Newari , c. early 10th century) was a saint and yogi in a number of Buddhist and Hindu traditions. He is traditionally considered the founder of hatha yoga as well as the author of some of its earliest texts. He is also seen as the founder of the natha sampradaya, having received the teachings from Shiva. He is especially associated with kaula shaivism. He is also one of the eighty-four mahasiddhas and considered the guru of Gorakshanath, another important figure in early hatha yoga. He is revered by both Hindus and Buddhists, and is sometimes regarded as an incarnation of Avalokiteśvara.