Xingyiquan (Chinese: 形意拳; pinyin: Xíng yì quán; Wade-Giles: Hsing I Ch'üan) is one of the major "internal" (nèijiā) Chinese martial arts. A practitioner of xingyiquan uses coordinated movements to generate bursts of power intended to overwhelm the opponent, simultaneously attacking and defending. Forms vary from school to school, but include barehanded sequences and versions of the same sequences with a variety of weapons. These sequences are based upon the movements and fighting behavior of a variety of animals. The training methods allow the student to progress through increasing difficulty in form sequences, timing and fighting strategy. The internal aspects of Xingyiquan are similar to, yet distinct from, those of Baguazhang and Tai chi chuan.