He manifests himself in any conceivable form wherever a being needs his help, especially when someone is menaced by water, demons, fire, or sword. Kuan-yin, whose name means "Who Contemplates the [Supplicating] Sound of the World", along with Samantabhadra, Kshitigarbha (Di-cang) and Manjushri (Wen-shu), is one of the four great bodishattvas of Buddhism. Guan-yin is identified as the male bodhisattva Avalokiteshvara, also known as Chenresi in Tibetan, "One Who Hears the Cries of the World".
In more recent representation, Guan-yin is often depicted with distinct feminine features, an effect of Taoistic and Tantric influences from the 8th to 10th century. She is often depicted as the Thousand Armed, Thousand Eyed bodhisattva, and later in a form inspired by the Virgin Mary figures from the West. In many representations, Guan-yin has a child on one arm or appears in the company of a maiden who holds a fish basked or is shown together with Wei-tuo. In other depictions Kuan-yin is shown standing on clouds or riding a dragon in front of a waterfall. As Guan-yin of the Southern Sea, he stands on a cliff in the midst of flaming waves and rescues shipwrecked persons from the sea (which symbolizes samsara, the cycle of birth, death, and rebirth). He usually holds a lotus blossom or a willow twig and a vase containing heavenly dew or the nectar of immortality.
--from Encyclopedia Mythica