Guan Yin (观世音菩萨) is a great bodhisattva in Buddhism and is famous by his compassion(慈悲心). 慈者与乐，悲者拔苦。无缘大慈，同体大悲。He also has the most fate of the Saha World(他和我们居住的这个娑婆世界众生最有缘). When you are in all kinds of dangers and feel no methods to relief yourself, if you say his name: 观世音菩萨 sincerely, then you can relief yourself.
I have several friends who like this bodhisattva very much. He has helped themseveral times.