History records that Yang Luchan trained with the Chen family for 18 years before he started to teach the art in Beijing, which strongly suggests that his art was based on, or heavily influenced by, the Chen family art. The Chen family are able to trace the development of their art back to Chen Wangting in the 17th century.
What is now known as "T'ai Chi Ch'uan" only appears to have received this appellation from around the mid-1800s. There was a scholar in the Imperial Court by the name of Ong Tong He, who witnessed a demonstration by Yang Luchan at a time before Yang had established his reputation as a teacher. Afterwards Ong wrote: "Hands holding Taiji shakes the whole world, a chest containing ultimate skill defeats a gathering of heroes." Before this time the art may have had a number of different names, and appears to have been generically described by outsiders as zhan quan (沾拳, "touch boxing"), mian quan (绵拳, "soft boxing") or shisan shi (十三式, "the thirteen techniques").
excerpted from Wikipedia, the free encyclopedia