Avalokiteshvara is a popular Buddha in many traditions and appears in many forms. In Tibet, he appears as Chenrezig, and appears in a female form as Kannon (sometimes Kanzeon) in Japan, Gwan-eum in Korea, Quan Am in Vietnam, and Quan Yin in China.
Within the Tibetan tradition, there are seemingly hundreds of tantric deities to practice, with varying colors, multiple arms and different expressions that range from pacifying to wrathful. Despite such a wide selection to choose from, Chenrezig can be easily overlooked and may seem almost common place.
One thing I’ve noticed, is that many of my own teachers keep recommending that people do Chenrezig practice or mantra during times of great difficulty. My feeling about this is that there really isn’t anything as immediate and powerful as generating compassion.