The exact origin of Hsing-I Chuan (Xing-Yi Quan) is unknown. The earliest written records of it can be traced to the 18th century to Ma Xueli of Henan Province and Dai Long Bang of Shanxi Province. Legend, however, credits the creation of Xing Yi to renowned Song Dynasty (960-1279 AD) general Yue Fei.
Characteristics and principles:
Hsing-I Chuan features aggressive shocking attacks and direct footwork. The linear nature of Hsing-I Chuan hints at both the military origins and the influence of spear technique alluded to in its mythology. Despite its hard, angular appearance, cultivating "soft" internal strength is essential to achieving power in Hsing-I Chuan. Also, the advanced practitioner always contains spirals within his movements, so even the seemingly direct and linear ones are circular on a very small scale. Such circles and spirals also exist in other martial arts, but Hsing-I (like Southern Praying Mantis) likes to keep them smaller than others.
The goal of the Hsing-I Chuan exponent is to reach the opponent quickly and drive powerfully through them in a single burst. The analogy with spear fighting is useful here. This is achieved by coordinating one's body as a single unit and the intense focusing of one's Intent (Yi).
Efficiency and economy of movement are the qualities of a Hsing-I stylist, and its direct fighting philosophy advocates simultaneous attack and defense. There are few kicks except for extremely low foot kicks (which avoids the hazards of balance involved with higher kicks) and some mid-level kicks, and techniques are prized for their working within key principles rather than aesthetic value.
Characteristics https://www.hsing-i.com/xingyi-characteristics
Internal Vs. External https://www.hsing-i.com/internal-vs-external