There are many variations and unique styles of Tai Chi. The five styles below are, I guess you could say, the original that form the bases of the many more variations out there. As far as is known it all started with the Chen style.
Created by Chen Wangting back in the 1670s.
Chen style emphasises what is known as spiral force. Movements are a mix of slow, soft, fast, and hard. Low stances and powerful moves, makes Chen the closest martial arts.
Created by Yang Lu-chan back in the early 19th century.
The most popular style to learn with its slow, gentle, graceful, circular movements. The perfect style for anyone wanting to quiet the remind yet can't sit still. Ultimate moving meditation.
Wu also known as Hao
Created by Wu Yuxiang and Hao Weizheng, who both studied the Yang and Chen styles.
Not a very well known style. Movements are slow and 'loose' and look very compact in appearance. Emphasis is on internal force and correct positioning.
Created by Wu Quan-you and Wu Jian-quan, although it shares the same name as the above Wu style it's very different. Slightly forward leaning posture and soft movements focused on redirecting incoming force.
The youngest of the five styles. Created by Sun Lu-tang.
Combining elements from Wu Hao Style and Xingyiquan and Baguaquan (two famous internal martial art styles). Characterised by "follow step", meaning whenever one foot moves forward or backwards the other foot follows. Making the movements seem to flow naturally.
The stances are kept high and there is also the addition of Qigong involved in the Sun style, making this style an easy one to learn and especially effective for healing and relaxation.